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diff --git a/docs/manual/modify.html b/docs/manual/modify.html deleted file mode 100644 index fe207d6..0000000 --- a/docs/manual/modify.html +++ /dev/null @@ -1,762 +0,0 @@ -<html> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> -<title>Modifying document data</title> -<link rel="stylesheet" href="../pugixml.css" type="text/css"> -<meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> -<link rel="home" href="../manual.html" title="pugixml 1.6"> -<link rel="up" href="../manual.html" title="pugixml 1.6"> -<link rel="prev" href="access.html" title="Accessing document data"> -<link rel="next" href="saving.html" title="Saving document"> -</head> -<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> -<table width="100%"><tr> -<td> -<a href="http://pugixml.org/">pugixml 1.6</a> manual | - <a href="../manual.html">Overview</a> | - <a href="install.html">Installation</a> | - Document: - <a href="dom.html">Object model</a> · <a href="loading.html">Loading</a> · <a href="access.html">Accessing</a> · <b>Modifying</b> · <a href="saving.html">Saving</a> | - <a href="xpath.html">XPath</a> | - <a href="apiref.html">API Reference</a> | - <a href="toc.html">Table of Contents</a> -</td> -<td width="*" align="right"><div class="spirit-nav"> -<a accesskey="p" href="access.html"><img src="../images/prev.png" alt="Prev"></a><a accesskey="u" href="../manual.html"><img src="../images/up.png" alt="Up"></a><a accesskey="h" href="../manual.html"><img src="../images/home.png" alt="Home"></a><a accesskey="n" href="saving.html"><img src="../images/next.png" alt="Next"></a> -</div></td> -</tr></table> -<hr> -<div class="section"> -<div class="titlepage"><div><div><h2 class="title" style="clear: both"> -<a name="manual.modify"></a><a class="link" href="modify.html" title="Modifying document data"> Modifying document data</a> -</h2></div></div></div> -<div class="toc"><dl class="toc"> -<dt><span class="section"><a href="modify.html#manual.modify.nodedata"> Setting node data</a></span></dt> -<dt><span class="section"><a href="modify.html#manual.modify.attrdata"> Setting attribute data</a></span></dt> -<dt><span class="section"><a href="modify.html#manual.modify.add"> Adding nodes/attributes</a></span></dt> -<dt><span class="section"><a href="modify.html#manual.modify.remove"> Removing nodes/attributes</a></span></dt> -<dt><span class="section"><a href="modify.html#manual.modify.text"> Working with text contents</a></span></dt> -<dt><span class="section"><a href="modify.html#manual.modify.clone"> Cloning nodes/attributes</a></span></dt> -<dt><span class="section"><a href="modify.html#manual.modify.move"> Moving nodes</a></span></dt> -<dt><span class="section"><a href="modify.html#manual.modify.fragments"> Assembling document from fragments</a></span></dt> -</dl></div> -<p> - The document in pugixml is fully mutable: you can completely change the document - structure and modify the data of nodes/attributes. This section provides documentation - for the relevant functions. All functions take care of memory management and - structural integrity themselves, so they always result in structurally valid - tree - however, it is possible to create an invalid XML tree (for example, - by adding two attributes with the same name or by setting attribute/node name - to empty/invalid string). Tree modification is optimized for performance and - for memory consumption, so if you have enough memory you can create documents - from scratch with pugixml and later save them to file/stream instead of relying - on error-prone manual text writing and without too much overhead. - </p> -<p> - All member functions that change node/attribute data or structure are non-constant - and thus can not be called on constant handles. However, you can easily convert - constant handle to non-constant one by simple assignment: <code class="computeroutput"><span class="keyword">void</span> - <span class="identifier">foo</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">n</span><span class="special">)</span> - <span class="special">{</span> <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">nc</span> <span class="special">=</span> <span class="identifier">n</span><span class="special">;</span> <span class="special">}</span></code>, so const-correctness - here mainly provides additional documentation. - </p> -<div class="section"> -<div class="titlepage"><div><div><h3 class="title"> -<a name="manual.modify.nodedata"></a><a class="link" href="modify.html#manual.modify.nodedata" title="Setting node data"> Setting node data</a> -</h3></div></div></div> -<a name="xml_node::set_name"></a><a name="xml_node::set_value"></a><p> - As discussed before, nodes can have name and value, both of which are strings. - Depending on node type, name or value may be absent. <a class="link" href="dom.html#node_document">node_document</a> - nodes do not have a name or value, <a class="link" href="dom.html#node_element">node_element</a> - and <a class="link" href="dom.html#node_declaration">node_declaration</a> nodes always - have a name but never have a value, <a class="link" href="dom.html#node_pcdata">node_pcdata</a>, - <a class="link" href="dom.html#node_cdata">node_cdata</a>, <a class="link" href="dom.html#node_comment">node_comment</a> - and <a class="link" href="dom.html#node_doctype">node_doctype</a> nodes never have a name - but always have a value (it may be empty though), <a class="link" href="dom.html#node_pi">node_pi</a> - nodes always have a name and a value (again, value may be empty). In order - to set node's name or value, you can use the following functions: - </p> -<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">set_name</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">set_value</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">rhs</span><span class="special">);</span> -</pre> -<p> - Both functions try to set the name/value to the specified string, and return - the operation result. The operation fails if the node can not have name or - value (for instance, when trying to call <code class="computeroutput"><span class="identifier">set_name</span></code> - on a <a class="link" href="dom.html#node_pcdata">node_pcdata</a> node), if the node handle - is null, or if there is insufficient memory to handle the request. The provided - string is copied into document managed memory and can be destroyed after - the function returns (for example, you can safely pass stack-allocated buffers - to these functions). The name/value content is not verified, so take care - to use only valid XML names, or the document may become malformed. - </p> -<p> - There is no equivalent of <a class="link" href="access.html#xml_node::child_value">child_value</a> - function for modifying text children of the node. - </p> -<p> - This is an example of setting node name and value (<a href="../samples/modify_base.cpp" target="_top">samples/modify_base.cpp</a>): - </p> -<p> - -</p> -<pre class="programlisting"><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">node</span> <span class="special">=</span> <span class="identifier">doc</span><span class="special">.</span><span class="identifier">child</span><span class="special">(</span><span class="string">"node"</span><span class="special">);</span> - -<span class="comment">// change node name -</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">node</span><span class="special">.</span><span class="identifier">set_name</span><span class="special">(</span><span class="string">"notnode"</span><span class="special">);</span> -<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">", new node name: "</span> <span class="special"><<</span> <span class="identifier">node</span><span class="special">.</span><span class="identifier">name</span><span class="special">()</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> - -<span class="comment">// change comment text -</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">doc</span><span class="special">.</span><span class="identifier">last_child</span><span class="special">().</span><span class="identifier">set_value</span><span class="special">(</span><span class="string">"useless comment"</span><span class="special">);</span> -<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">", new comment text: "</span> <span class="special"><<</span> <span class="identifier">doc</span><span class="special">.</span><span class="identifier">last_child</span><span class="special">().</span><span class="identifier">value</span><span class="special">()</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> - -<span class="comment">// we can't change value of the element or name of the comment -</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">node</span><span class="special">.</span><span class="identifier">set_value</span><span class="special">(</span><span class="string">"1"</span><span class="special">)</span> <span class="special"><<</span> <span class="string">", "</span> <span class="special"><<</span> <span class="identifier">doc</span><span class="special">.</span><span class="identifier">last_child</span><span class="special">().</span><span class="identifier">set_name</span><span class="special">(</span><span class="string">"2"</span><span class="special">)</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> -</pre> -<p> - </p> -</div> -<div class="section"> -<div class="titlepage"><div><div><h3 class="title"> -<a name="manual.modify.attrdata"></a><a class="link" href="modify.html#manual.modify.attrdata" title="Setting attribute data"> Setting attribute data</a> -</h3></div></div></div> -<a name="xml_attribute::set_name"></a><a name="xml_attribute::set_value"></a><p> - All attributes have name and value, both of which are strings (value may - be empty). You can set them with the following functions: - </p> -<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="identifier">set_name</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="identifier">set_value</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">rhs</span><span class="special">);</span> -</pre> -<p> - Both functions try to set the name/value to the specified string, and return - the operation result. The operation fails if the attribute handle is null, - or if there is insufficient memory to handle the request. The provided string - is copied into document managed memory and can be destroyed after the function - returns (for example, you can safely pass stack-allocated buffers to these - functions). The name/value content is not verified, so take care to use only - valid XML names, or the document may become malformed. - </p> -<p> - In addition to string functions, several functions are provided for handling - attributes with numbers and booleans as values: - </p> -<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="identifier">set_value</span><span class="special">(</span><span class="keyword">int</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="identifier">set_value</span><span class="special">(</span><span class="keyword">unsigned</span> <span class="keyword">int</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="identifier">set_value</span><span class="special">(</span><span class="keyword">double</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="identifier">set_value</span><span class="special">(</span><span class="keyword">float</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="identifier">set_value</span><span class="special">(</span><span class="keyword">bool</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="identifier">set_value</span><span class="special">(</span><span class="keyword">long</span> <span class="keyword">long</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="identifier">set_value</span><span class="special">(</span><span class="keyword">unsigned</span> <span class="keyword">long</span> <span class="keyword">long</span> <span class="identifier">rhs</span><span class="special">);</span> -</pre> -<p> - The above functions convert the argument to string and then call the base - <code class="computeroutput"><span class="identifier">set_value</span></code> function. Integers - are converted to a decimal form, floating-point numbers are converted to - either decimal or scientific form, depending on the number magnitude, boolean - values are converted to either <code class="computeroutput"><span class="string">"true"</span></code> - or <code class="computeroutput"><span class="string">"false"</span></code>. - </p> -<div class="caution"><table border="0" summary="Caution"> -<tr> -<td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="../images/caution.png"></td> -<th align="left">Caution</th> -</tr> -<tr><td align="left" valign="top"><p> - Number conversion functions depend on current C locale as set with <code class="computeroutput"><span class="identifier">setlocale</span></code>, so may generate unexpected - results if the locale is different from <code class="computeroutput"><span class="string">"C"</span></code>. - </p></td></tr> -</table></div> -<div class="note"><table border="0" summary="Note"> -<tr> -<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../images/note.png"></td> -<th align="left">Note</th> -</tr> -<tr><td align="left" valign="top"><p> - <code class="computeroutput"><span class="identifier">set_value</span></code> overloads with - <code class="computeroutput"><span class="keyword">long</span> <span class="keyword">long</span></code> - type are only available if your platform has reliable support for the type, - including string conversions. - </p></td></tr> -</table></div> -<a name="xml_attribute::assign"></a><p> - For convenience, all <code class="computeroutput"><span class="identifier">set_value</span></code> - functions have the corresponding assignment operators: - </p> -<pre class="programlisting"><span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">int</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">unsigned</span> <span class="keyword">int</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">double</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">float</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">bool</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">long</span> <span class="keyword">long</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">unsigned</span> <span class="keyword">long</span> <span class="keyword">long</span> <span class="identifier">rhs</span><span class="special">);</span> -</pre> -<p> - These operators simply call the right <code class="computeroutput"><span class="identifier">set_value</span></code> - function and return the attribute they're called on; the return value of - <code class="computeroutput"><span class="identifier">set_value</span></code> is ignored, so - errors are ignored. - </p> -<p> - This is an example of setting attribute name and value (<a href="../samples/modify_base.cpp" target="_top">samples/modify_base.cpp</a>): - </p> -<p> - -</p> -<pre class="programlisting"><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_attribute</span> <span class="identifier">attr</span> <span class="special">=</span> <span class="identifier">node</span><span class="special">.</span><span class="identifier">attribute</span><span class="special">(</span><span class="string">"id"</span><span class="special">);</span> - -<span class="comment">// change attribute name/value -</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">attr</span><span class="special">.</span><span class="identifier">set_name</span><span class="special">(</span><span class="string">"key"</span><span class="special">)</span> <span class="special"><<</span> <span class="string">", "</span> <span class="special"><<</span> <span class="identifier">attr</span><span class="special">.</span><span class="identifier">set_value</span><span class="special">(</span><span class="string">"345"</span><span class="special">);</span> -<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">", new attribute: "</span> <span class="special"><<</span> <span class="identifier">attr</span><span class="special">.</span><span class="identifier">name</span><span class="special">()</span> <span class="special"><<</span> <span class="string">"="</span> <span class="special"><<</span> <span class="identifier">attr</span><span class="special">.</span><span class="identifier">value</span><span class="special">()</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> - -<span class="comment">// we can use numbers or booleans -</span><span class="identifier">attr</span><span class="special">.</span><span class="identifier">set_value</span><span class="special">(</span><span class="number">1.234</span><span class="special">);</span> -<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"new attribute value: "</span> <span class="special"><<</span> <span class="identifier">attr</span><span class="special">.</span><span class="identifier">value</span><span class="special">()</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> - -<span class="comment">// we can also use assignment operators for more concise code -</span><span class="identifier">attr</span> <span class="special">=</span> <span class="keyword">true</span><span class="special">;</span> -<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"final attribute value: "</span> <span class="special"><<</span> <span class="identifier">attr</span><span class="special">.</span><span class="identifier">value</span><span class="special">()</span> <span class="special"><<</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span> -</pre> -<p> - </p> -</div> -<div class="section"> -<div class="titlepage"><div><div><h3 class="title"> -<a name="manual.modify.add"></a><a class="link" href="modify.html#manual.modify.add" title="Adding nodes/attributes"> Adding nodes/attributes</a> -</h3></div></div></div> -<a name="xml_node::prepend_attribute"></a><a name="xml_node::append_attribute"></a><a name="xml_node::insert_attribute_after"></a><a name="xml_node::insert_attribute_before"></a><a name="xml_node::prepend_child"></a><a name="xml_node::append_child"></a><a name="xml_node::insert_child_after"></a><a name="xml_node::insert_child_before"></a><p> - Nodes and attributes do not exist without a document tree, so you can't create - them without adding them to some document. A node or attribute can be created - at the end of node/attribute list or before/after some other node: - </p> -<pre class="programlisting"><span class="identifier">xml_attribute</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">append_attribute</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">name</span><span class="special">);</span> -<span class="identifier">xml_attribute</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">prepend_attribute</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">name</span><span class="special">);</span> -<span class="identifier">xml_attribute</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_attribute_after</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">name</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">attr</span><span class="special">);</span> -<span class="identifier">xml_attribute</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_attribute_before</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">name</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">attr</span><span class="special">);</span> - -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">append_child</span><span class="special">(</span><span class="identifier">xml_node_type</span> <span class="identifier">type</span> <span class="special">=</span> <span class="identifier">node_element</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">prepend_child</span><span class="special">(</span><span class="identifier">xml_node_type</span> <span class="identifier">type</span> <span class="special">=</span> <span class="identifier">node_element</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_child_after</span><span class="special">(</span><span class="identifier">xml_node_type</span> <span class="identifier">type</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">node</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_child_before</span><span class="special">(</span><span class="identifier">xml_node_type</span> <span class="identifier">type</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">node</span><span class="special">);</span> - -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">append_child</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">name</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">prepend_child</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">name</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_child_after</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">name</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">node</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_child_before</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">name</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">node</span><span class="special">);</span> -</pre> -<p> - <code class="computeroutput"><span class="identifier">append_attribute</span></code> and <code class="computeroutput"><span class="identifier">append_child</span></code> create a new node/attribute - at the end of the corresponding list of the node the method is called on; - <code class="computeroutput"><span class="identifier">prepend_attribute</span></code> and <code class="computeroutput"><span class="identifier">prepend_child</span></code> create a new node/attribute - at the beginning of the list; <code class="computeroutput"><span class="identifier">insert_attribute_after</span></code>, - <code class="computeroutput"><span class="identifier">insert_attribute_before</span></code>, - <code class="computeroutput"><span class="identifier">insert_child_after</span></code> and <code class="computeroutput"><span class="identifier">insert_attribute_before</span></code> add the node/attribute - before or after the specified node/attribute. - </p> -<p> - Attribute functions create an attribute with the specified name; you can - specify the empty name and change the name later if you want to. Node functions - with the <code class="computeroutput"><span class="identifier">type</span></code> argument create - the node with the specified type; since node type can't be changed, you have - to know the desired type beforehand. Also note that not all types can be - added as children; see below for clarification. Node functions with the - <code class="computeroutput"><span class="identifier">name</span></code> argument create the - element node (<a class="link" href="dom.html#node_element">node_element</a>) with the - specified name. - </p> -<p> - All functions return the handle to the created object on success, and null - handle on failure. There are several reasons for failure: - </p> -<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> -<li class="listitem"> - Adding fails if the target node is null; - </li> -<li class="listitem"> - Only <a class="link" href="dom.html#node_element">node_element</a> nodes can contain - attributes, so attribute adding fails if node is not an element; - </li> -<li class="listitem"> - Only <a class="link" href="dom.html#node_document">node_document</a> and <a class="link" href="dom.html#node_element">node_element</a> - nodes can contain children, so child node adding fails if the target - node is not an element or a document; - </li> -<li class="listitem"> - <a class="link" href="dom.html#node_document">node_document</a> and <a class="link" href="dom.html#node_null">node_null</a> - nodes can not be inserted as children, so passing <a class="link" href="dom.html#node_document">node_document</a> - or <a class="link" href="dom.html#node_null">node_null</a> value as <code class="computeroutput"><span class="identifier">type</span></code> results in operation failure; - </li> -<li class="listitem"> - <a class="link" href="dom.html#node_declaration">node_declaration</a> nodes can only - be added as children of the document node; attempt to insert declaration - node as a child of an element node fails; - </li> -<li class="listitem"> - Adding node/attribute results in memory allocation, which may fail; - </li> -<li class="listitem"> - Insertion functions fail if the specified node or attribute is null or - is not in the target node's children/attribute list. - </li> -</ul></div> -<p> - Even if the operation fails, the document remains in consistent state, but - the requested node/attribute is not added. - </p> -<div class="caution"><table border="0" summary="Caution"> -<tr> -<td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="../images/caution.png"></td> -<th align="left">Caution</th> -</tr> -<tr><td align="left" valign="top"><p> - attribute() and child() functions do not add attributes or nodes to the - tree, so code like <code class="computeroutput"><span class="identifier">node</span><span class="special">.</span><span class="identifier">attribute</span><span class="special">(</span><span class="string">"id"</span><span class="special">)</span> <span class="special">=</span> <span class="number">123</span><span class="special">;</span></code> will not do anything if <code class="computeroutput"><span class="identifier">node</span></code> does not have an attribute with - name <code class="computeroutput"><span class="string">"id"</span></code>. Make sure - you're operating with existing attributes/nodes by adding them if necessary. - </p></td></tr> -</table></div> -<p> - This is an example of adding new attributes/nodes to the document (<a href="../samples/modify_add.cpp" target="_top">samples/modify_add.cpp</a>): - </p> -<p> - -</p> -<pre class="programlisting"><span class="comment">// add node with some name -</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">node</span> <span class="special">=</span> <span class="identifier">doc</span><span class="special">.</span><span class="identifier">append_child</span><span class="special">(</span><span class="string">"node"</span><span class="special">);</span> - -<span class="comment">// add description node with text child -</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">descr</span> <span class="special">=</span> <span class="identifier">node</span><span class="special">.</span><span class="identifier">append_child</span><span class="special">(</span><span class="string">"description"</span><span class="special">);</span> -<span class="identifier">descr</span><span class="special">.</span><span class="identifier">append_child</span><span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">node_pcdata</span><span class="special">).</span><span class="identifier">set_value</span><span class="special">(</span><span class="string">"Simple node"</span><span class="special">);</span> - -<span class="comment">// add param node before the description -</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">param</span> <span class="special">=</span> <span class="identifier">node</span><span class="special">.</span><span class="identifier">insert_child_before</span><span class="special">(</span><span class="string">"param"</span><span class="special">,</span> <span class="identifier">descr</span><span class="special">);</span> - -<span class="comment">// add attributes to param node -</span><span class="identifier">param</span><span class="special">.</span><span class="identifier">append_attribute</span><span class="special">(</span><span class="string">"name"</span><span class="special">)</span> <span class="special">=</span> <span class="string">"version"</span><span class="special">;</span> -<span class="identifier">param</span><span class="special">.</span><span class="identifier">append_attribute</span><span class="special">(</span><span class="string">"value"</span><span class="special">)</span> <span class="special">=</span> <span class="number">1.1</span><span class="special">;</span> -<span class="identifier">param</span><span class="special">.</span><span class="identifier">insert_attribute_after</span><span class="special">(</span><span class="string">"type"</span><span class="special">,</span> <span class="identifier">param</span><span class="special">.</span><span class="identifier">attribute</span><span class="special">(</span><span class="string">"name"</span><span class="special">))</span> <span class="special">=</span> <span class="string">"float"</span><span class="special">;</span> -</pre> -<p> - </p> -</div> -<div class="section"> -<div class="titlepage"><div><div><h3 class="title"> -<a name="manual.modify.remove"></a><a class="link" href="modify.html#manual.modify.remove" title="Removing nodes/attributes"> Removing nodes/attributes</a> -</h3></div></div></div> -<a name="xml_node::remove_attribute"></a><a name="xml_node::remove_child"></a><p> - If you do not want your document to contain some node or attribute, you can - remove it with one of the following functions: - </p> -<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">remove_attribute</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">a</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">remove_child</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">n</span><span class="special">);</span> -</pre> -<p> - <code class="computeroutput"><span class="identifier">remove_attribute</span></code> removes - the attribute from the attribute list of the node, and returns the operation - result. <code class="computeroutput"><span class="identifier">remove_child</span></code> removes - the child node with the entire subtree (including all descendant nodes and - attributes) from the document, and returns the operation result. Removing - fails if one of the following is true: - </p> -<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> -<li class="listitem"> - The node the function is called on is null; - </li> -<li class="listitem"> - The attribute/node to be removed is null; - </li> -<li class="listitem"> - The attribute/node to be removed is not in the node's attribute/child - list. - </li> -</ul></div> -<p> - Removing the attribute or node invalidates all handles to the same underlying - object, and also invalidates all iterators pointing to the same object. Removing - node also invalidates all past-the-end iterators to its attribute or child - node list. Be careful to ensure that all such handles and iterators either - do not exist or are not used after the attribute/node is removed. - </p> -<p> - If you want to remove the attribute or child node by its name, two additional - helper functions are available: - </p> -<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">remove_attribute</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">name</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">remove_child</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">name</span><span class="special">);</span> -</pre> -<p> - These functions look for the first attribute or child with the specified - name, and then remove it, returning the result. If there is no attribute - or child with such name, the function returns <code class="computeroutput"><span class="keyword">false</span></code>; - if there are two nodes with the given name, only the first node is deleted. - If you want to delete all nodes with the specified name, you can use code - like this: <code class="computeroutput"><span class="keyword">while</span> <span class="special">(</span><span class="identifier">node</span><span class="special">.</span><span class="identifier">remove_child</span><span class="special">(</span><span class="string">"tool"</span><span class="special">))</span> <span class="special">;</span></code>. - </p> -<p> - This is an example of removing attributes/nodes from the document (<a href="../samples/modify_remove.cpp" target="_top">samples/modify_remove.cpp</a>): - </p> -<p> - -</p> -<pre class="programlisting"><span class="comment">// remove description node with the whole subtree -</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">node</span> <span class="special">=</span> <span class="identifier">doc</span><span class="special">.</span><span class="identifier">child</span><span class="special">(</span><span class="string">"node"</span><span class="special">);</span> -<span class="identifier">node</span><span class="special">.</span><span class="identifier">remove_child</span><span class="special">(</span><span class="string">"description"</span><span class="special">);</span> - -<span class="comment">// remove id attribute -</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">param</span> <span class="special">=</span> <span class="identifier">node</span><span class="special">.</span><span class="identifier">child</span><span class="special">(</span><span class="string">"param"</span><span class="special">);</span> -<span class="identifier">param</span><span class="special">.</span><span class="identifier">remove_attribute</span><span class="special">(</span><span class="string">"value"</span><span class="special">);</span> - -<span class="comment">// we can also remove nodes/attributes by handles -</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_attribute</span> <span class="identifier">id</span> <span class="special">=</span> <span class="identifier">param</span><span class="special">.</span><span class="identifier">attribute</span><span class="special">(</span><span class="string">"name"</span><span class="special">);</span> -<span class="identifier">param</span><span class="special">.</span><span class="identifier">remove_attribute</span><span class="special">(</span><span class="identifier">id</span><span class="special">);</span> -</pre> -<p> - </p> -</div> -<div class="section"> -<div class="titlepage"><div><div><h3 class="title"> -<a name="manual.modify.text"></a><a class="link" href="modify.html#manual.modify.text" title="Working with text contents"> Working with text contents</a> -</h3></div></div></div> -<p> - pugixml provides a special class, <code class="computeroutput"><span class="identifier">xml_text</span></code>, - to work with text contents stored as a value of some node, i.e. <code class="computeroutput"><span class="special"><</span><span class="identifier">node</span><span class="special">><</span><span class="identifier">description</span><span class="special">></span><span class="identifier">This</span> <span class="identifier">is</span> <span class="identifier">a</span> <span class="identifier">node</span><span class="special"></</span><span class="identifier">description</span><span class="special">></</span><span class="identifier">node</span><span class="special">></span></code>. - Working with text objects to retrieve data is described in <a class="link" href="access.html#manual.access.text" title="Working with text contents">the - documentation for accessing document data</a>; this section describes - the modification interface of <code class="computeroutput"><span class="identifier">xml_text</span></code>. - </p> -<a name="xml_text::set"></a><p> - Once you have an <code class="computeroutput"><span class="identifier">xml_text</span></code> - object, you can set the text contents using the following function: - </p> -<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="identifier">set</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">rhs</span><span class="special">);</span> -</pre> -<p> - This function tries to set the contents to the specified string, and returns - the operation result. The operation fails if the text object was retrieved - from a node that can not have a value and is not an element node (i.e. it - is a <a class="link" href="dom.html#node_declaration">node_declaration</a> node), if the - text object is empty, or if there is insufficient memory to handle the request. - The provided string is copied into document managed memory and can be destroyed - after the function returns (for example, you can safely pass stack-allocated - buffers to this function). Note that if the text object was retrieved from - an element node, this function creates the PCDATA child node if necessary - (i.e. if the element node does not have a PCDATA/CDATA child already). - </p> -<a name="xml_text::set_value"></a><p> - In addition to a string function, several functions are provided for handling - text with numbers and booleans as contents: - </p> -<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="identifier">set</span><span class="special">(</span><span class="keyword">int</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="identifier">set</span><span class="special">(</span><span class="keyword">unsigned</span> <span class="keyword">int</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="identifier">set</span><span class="special">(</span><span class="keyword">double</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="identifier">set</span><span class="special">(</span><span class="keyword">float</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="identifier">set</span><span class="special">(</span><span class="keyword">bool</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="identifier">set</span><span class="special">(</span><span class="keyword">long</span> <span class="keyword">long</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="keyword">bool</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="identifier">set</span><span class="special">(</span><span class="keyword">unsigned</span> <span class="keyword">long</span> <span class="keyword">long</span> <span class="identifier">rhs</span><span class="special">);</span> -</pre> -<p> - The above functions convert the argument to string and then call the base - <code class="computeroutput"><span class="identifier">set</span></code> function. These functions - have the same semantics as similar <code class="computeroutput"><span class="identifier">xml_attribute</span></code> - functions. You can <a class="link" href="modify.html#xml_attribute::set_value">refer to documentation - for the attribute functions</a> for details. - </p> -<a name="xml_text::assign"></a><p> - For convenience, all <code class="computeroutput"><span class="identifier">set</span></code> - functions have the corresponding assignment operators: - </p> -<pre class="programlisting"><span class="identifier">xml_text</span><span class="special">&</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">const</span> <span class="identifier">char_t</span><span class="special">*</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_text</span><span class="special">&</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">int</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_text</span><span class="special">&</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">unsigned</span> <span class="keyword">int</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_text</span><span class="special">&</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">double</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_text</span><span class="special">&</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">float</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_text</span><span class="special">&</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">bool</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_text</span><span class="special">&</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">long</span> <span class="keyword">long</span> <span class="identifier">rhs</span><span class="special">);</span> -<span class="identifier">xml_text</span><span class="special">&</span> <span class="identifier">xml_text</span><span class="special">::</span><span class="keyword">operator</span><span class="special">=(</span><span class="keyword">unsigned</span> <span class="keyword">long</span> <span class="keyword">long</span> <span class="identifier">rhs</span><span class="special">);</span> -</pre> -<p> - These operators simply call the right <code class="computeroutput"><span class="identifier">set</span></code> - function and return the attribute they're called on; the return value of - <code class="computeroutput"><span class="identifier">set</span></code> is ignored, so errors - are ignored. - </p> -<p> - This is an example of using <code class="computeroutput"><span class="identifier">xml_text</span></code> - object to modify text contents (<a href="../samples/text.cpp" target="_top">samples/text.cpp</a>): - </p> -<p> - -</p> -<pre class="programlisting"><span class="comment">// change project version -</span><span class="identifier">project</span><span class="special">.</span><span class="identifier">child</span><span class="special">(</span><span class="string">"version"</span><span class="special">).</span><span class="identifier">text</span><span class="special">()</span> <span class="special">=</span> <span class="number">1.2</span><span class="special">;</span> - -<span class="comment">// add description element and set the contents -</span><span class="comment">// note that we do not have to explicitly add the node_pcdata child -</span><span class="identifier">project</span><span class="special">.</span><span class="identifier">append_child</span><span class="special">(</span><span class="string">"description"</span><span class="special">).</span><span class="identifier">text</span><span class="special">().</span><span class="identifier">set</span><span class="special">(</span><span class="string">"a test project"</span><span class="special">);</span> -</pre> -<p> - </p> -</div> -<div class="section"> -<div class="titlepage"><div><div><h3 class="title"> -<a name="manual.modify.clone"></a><a class="link" href="modify.html#manual.modify.clone" title="Cloning nodes/attributes"> Cloning nodes/attributes</a> -</h3></div></div></div> -<a name="xml_node::prepend_copy"></a><a name="xml_node::append_copy"></a><a name="xml_node::insert_copy_after"></a><a name="xml_node::insert_copy_before"></a><p> - With the help of previously described functions, it is possible to create - trees with any contents and structure, including cloning the existing data. - However since this is an often needed operation, pugixml provides built-in - node/attribute cloning facilities. Since nodes and attributes do not exist - without a document tree, you can't create a standalone copy - you have to - immediately insert it somewhere in the tree. For this, you can use one of - the following functions: - </p> -<pre class="programlisting"><span class="identifier">xml_attribute</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">append_copy</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">proto</span><span class="special">);</span> -<span class="identifier">xml_attribute</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">prepend_copy</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">proto</span><span class="special">);</span> -<span class="identifier">xml_attribute</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_copy_after</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">proto</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">attr</span><span class="special">);</span> -<span class="identifier">xml_attribute</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_copy_before</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">proto</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_attribute</span><span class="special">&</span> <span class="identifier">attr</span><span class="special">);</span> - -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">append_copy</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">proto</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">prepend_copy</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">proto</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_copy_after</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">proto</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">node</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_copy_before</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">proto</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">node</span><span class="special">);</span> -</pre> -<p> - These functions mirror the structure of <code class="computeroutput"><span class="identifier">append_child</span></code>, - <code class="computeroutput"><span class="identifier">prepend_child</span></code>, <code class="computeroutput"><span class="identifier">insert_child_before</span></code> and related functions - - they take the handle to the prototype object, which is to be cloned, insert - a new attribute/node at the appropriate place, and then copy the attribute - data or the whole node subtree to the new object. The functions return the - handle to the resulting duplicate object, or null handle on failure. - </p> -<p> - The attribute is copied along with the name and value; the node is copied - along with its type, name and value; additionally attribute list and all - children are recursively cloned, resulting in the deep subtree clone. The - prototype object can be a part of the same document, or a part of any other - document. - </p> -<p> - The failure conditions resemble those of <code class="computeroutput"><span class="identifier">append_child</span></code>, - <code class="computeroutput"><span class="identifier">insert_child_before</span></code> and related - functions, <a class="link" href="modify.html#xml_node::append_child">consult their documentation - for more information</a>. There are additional caveats specific to cloning - functions: - </p> -<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> -<li class="listitem"> - Cloning null handles results in operation failure; - </li> -<li class="listitem"> - Node cloning starts with insertion of the node of the same type as that - of the prototype; for this reason, cloning functions can not be directly - used to clone entire documents, since <a class="link" href="dom.html#node_document">node_document</a> - is not a valid insertion type. The example below provides a workaround. - </li> -<li class="listitem"> - It is possible to copy a subtree as a child of some node inside this - subtree, i.e. <code class="computeroutput"><span class="identifier">node</span><span class="special">.</span><span class="identifier">append_copy</span><span class="special">(</span><span class="identifier">node</span><span class="special">.</span><span class="identifier">parent</span><span class="special">().</span><span class="identifier">parent</span><span class="special">());</span></code>. - This is a valid operation, and it results in a clone of the subtree in - the state before cloning started, i.e. no infinite recursion takes place. - </li> -</ul></div> -<p> - This is an example with one possible implementation of include tags in XML - (<a href="../samples/include.cpp" target="_top">samples/include.cpp</a>). It illustrates - node cloning and usage of other document modification functions: - </p> -<p> - -</p> -<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">load_preprocess</span><span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_document</span><span class="special">&</span> <span class="identifier">doc</span><span class="special">,</span> <span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">path</span><span class="special">);</span> - -<span class="keyword">bool</span> <span class="identifier">preprocess</span><span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">node</span><span class="special">)</span> -<span class="special">{</span> - <span class="keyword">for</span> <span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">child</span> <span class="special">=</span> <span class="identifier">node</span><span class="special">.</span><span class="identifier">first_child</span><span class="special">();</span> <span class="identifier">child</span><span class="special">;</span> <span class="special">)</span> - <span class="special">{</span> - <span class="keyword">if</span> <span class="special">(</span><span class="identifier">child</span><span class="special">.</span><span class="identifier">type</span><span class="special">()</span> <span class="special">==</span> <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">node_pi</span> <span class="special">&&</span> <span class="identifier">strcmp</span><span class="special">(</span><span class="identifier">child</span><span class="special">.</span><span class="identifier">name</span><span class="special">(),</span> <span class="string">"include"</span><span class="special">)</span> <span class="special">==</span> <span class="number">0</span><span class="special">)</span> - <span class="special">{</span> - <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">include</span> <span class="special">=</span> <span class="identifier">child</span><span class="special">;</span> - - <span class="comment">// load new preprocessed document (note: ideally this should handle relative paths) -</span> <span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">path</span> <span class="special">=</span> <span class="identifier">include</span><span class="special">.</span><span class="identifier">value</span><span class="special">();</span> - - <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_document</span> <span class="identifier">doc</span><span class="special">;</span> - <span class="keyword">if</span> <span class="special">(!</span><span class="identifier">load_preprocess</span><span class="special">(</span><span class="identifier">doc</span><span class="special">,</span> <span class="identifier">path</span><span class="special">))</span> <span class="keyword">return</span> <span class="keyword">false</span><span class="special">;</span> - - <span class="comment">// insert the comment marker above include directive -</span> <span class="identifier">node</span><span class="special">.</span><span class="identifier">insert_child_before</span><span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">node_comment</span><span class="special">,</span> <span class="identifier">include</span><span class="special">).</span><span class="identifier">set_value</span><span class="special">(</span><span class="identifier">path</span><span class="special">);</span> - - <span class="comment">// copy the document above the include directive (this retains the original order!) -</span> <span class="keyword">for</span> <span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">ic</span> <span class="special">=</span> <span class="identifier">doc</span><span class="special">.</span><span class="identifier">first_child</span><span class="special">();</span> <span class="identifier">ic</span><span class="special">;</span> <span class="identifier">ic</span> <span class="special">=</span> <span class="identifier">ic</span><span class="special">.</span><span class="identifier">next_sibling</span><span class="special">())</span> - <span class="special">{</span> - <span class="identifier">node</span><span class="special">.</span><span class="identifier">insert_copy_before</span><span class="special">(</span><span class="identifier">ic</span><span class="special">,</span> <span class="identifier">include</span><span class="special">);</span> - <span class="special">}</span> - - <span class="comment">// remove the include node and move to the next child -</span> <span class="identifier">child</span> <span class="special">=</span> <span class="identifier">child</span><span class="special">.</span><span class="identifier">next_sibling</span><span class="special">();</span> - - <span class="identifier">node</span><span class="special">.</span><span class="identifier">remove_child</span><span class="special">(</span><span class="identifier">include</span><span class="special">);</span> - <span class="special">}</span> - <span class="keyword">else</span> - <span class="special">{</span> - <span class="keyword">if</span> <span class="special">(!</span><span class="identifier">preprocess</span><span class="special">(</span><span class="identifier">child</span><span class="special">))</span> <span class="keyword">return</span> <span class="keyword">false</span><span class="special">;</span> - - <span class="identifier">child</span> <span class="special">=</span> <span class="identifier">child</span><span class="special">.</span><span class="identifier">next_sibling</span><span class="special">();</span> - <span class="special">}</span> - <span class="special">}</span> - - <span class="keyword">return</span> <span class="keyword">true</span><span class="special">;</span> -<span class="special">}</span> - -<span class="keyword">bool</span> <span class="identifier">load_preprocess</span><span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_document</span><span class="special">&</span> <span class="identifier">doc</span><span class="special">,</span> <span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">path</span><span class="special">)</span> -<span class="special">{</span> - <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_parse_result</span> <span class="identifier">result</span> <span class="special">=</span> <span class="identifier">doc</span><span class="special">.</span><span class="identifier">load_file</span><span class="special">(</span><span class="identifier">path</span><span class="special">,</span> <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">parse_default</span> <span class="special">|</span> <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">parse_pi</span><span class="special">);</span> <span class="comment">// for <?include?> -</span> - <span class="keyword">return</span> <span class="identifier">result</span> <span class="special">?</span> <span class="identifier">preprocess</span><span class="special">(</span><span class="identifier">doc</span><span class="special">)</span> <span class="special">:</span> <span class="keyword">false</span><span class="special">;</span> -<span class="special">}</span> -</pre> -<p> - </p> -</div> -<div class="section"> -<div class="titlepage"><div><div><h3 class="title"> -<a name="manual.modify.move"></a><a class="link" href="modify.html#manual.modify.move" title="Moving nodes"> Moving nodes</a> -</h3></div></div></div> -<a name="xml_node::prepend_move"></a><a name="xml_node::append_move"></a><a name="xml_node::insert_move_after"></a><a name="xml_node::insert_move_before"></a><p> - Sometimes instead of cloning a node you need to move an existing node to - a different position in a tree. This can be accomplished by copying the node - and removing the original; however, this is expensive since it results in - a lot of extra operations. For moving nodes within the same document tree, - you can use of the following functions instead: - </p> -<pre class="programlisting"><span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">append_move</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">moved</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">prepend_move</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">moved</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_move_after</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">moved</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">node</span><span class="special">);</span> -<span class="identifier">xml_node</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">insert_move_before</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">moved</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">xml_node</span><span class="special">&</span> <span class="identifier">node</span><span class="special">);</span> -</pre> -<p> - These functions mirror the structure of <code class="computeroutput"><span class="identifier">append_copy</span></code>, - <code class="computeroutput"><span class="identifier">prepend_copy</span></code>, <code class="computeroutput"><span class="identifier">insert_copy_before</span></code> and <code class="computeroutput"><span class="identifier">insert_copy_after</span></code> - - they take the handle to the moved object and move it to the appropriate - place with all attributes and/or child nodes. The functions return the handle - to the resulting object (which is the same as the moved object), or null - handle on failure. - </p> -<p> - The failure conditions resemble those of <code class="computeroutput"><span class="identifier">append_child</span></code>, - <code class="computeroutput"><span class="identifier">insert_child_before</span></code> and related - functions, <a class="link" href="modify.html#xml_node::append_child">consult their documentation - for more information</a>. There are additional caveats specific to moving - functions: - </p> -<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> -<li class="listitem"> - Moving null handles results in operation failure; - </li> -<li class="listitem"> - Moving is only possible for nodes that belong to the same document; attempting - to move nodes between documents will fail. - </li> -<li class="listitem"> - <code class="computeroutput"><span class="identifier">insert_move_after</span></code> and - <code class="computeroutput"><span class="identifier">insert_move_before</span></code> functions - fail if the moved node is the same as the <code class="computeroutput"><span class="identifier">node</span></code> - argument (this operation would be a no-op otherwise). - </li> -<li class="listitem"> - It is impossible to move a subtree to a child of some node inside this - subtree, i.e. <code class="computeroutput"><span class="identifier">node</span><span class="special">.</span><span class="identifier">append_move</span><span class="special">(</span><span class="identifier">node</span><span class="special">.</span><span class="identifier">parent</span><span class="special">().</span><span class="identifier">parent</span><span class="special">());</span></code> - will fail. - </li> -</ul></div> -</div> -<div class="section"> -<div class="titlepage"><div><div><h3 class="title"> -<a name="manual.modify.fragments"></a><a class="link" href="modify.html#manual.modify.fragments" title="Assembling document from fragments"> Assembling document from fragments</a> -</h3></div></div></div> -<a name="xml_node::append_buffer"></a><p> - pugixml provides several ways to assemble an XML document from other XML - documents. Assuming there is a set of document fragments, represented as - in-memory buffers, the implementation choices are as follows: - </p> -<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"> - Use a temporary document to parse the data from a string, then clone - the nodes to a destination node. For example: - </li></ul></div> -<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">append_fragment</span><span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">target</span><span class="special">,</span> <span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">buffer</span><span class="special">,</span> <span class="identifier">size_t</span> <span class="identifier">size</span><span class="special">)</span> -<span class="special">{</span> - <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_document</span> <span class="identifier">doc</span><span class="special">;</span> - <span class="keyword">if</span> <span class="special">(!</span><span class="identifier">doc</span><span class="special">.</span><span class="identifier">load_buffer</span><span class="special">(</span><span class="identifier">buffer</span><span class="special">,</span> <span class="identifier">size</span><span class="special">))</span> <span class="keyword">return</span> <span class="keyword">false</span><span class="special">;</span> - - <span class="keyword">for</span> <span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">child</span> <span class="special">=</span> <span class="identifier">doc</span><span class="special">.</span><span class="identifier">first_child</span><span class="special">();</span> <span class="identifier">child</span><span class="special">;</span> <span class="identifier">child</span> <span class="special">=</span> <span class="identifier">child</span><span class="special">.</span><span class="identifier">next_sibling</span><span class="special">())</span> - <span class="identifier">target</span><span class="special">.</span><span class="identifier">append_copy</span><span class="special">(</span><span class="identifier">child</span><span class="special">);</span> -<span class="special">}</span> -</pre> -<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"> - Cache the parsing step - instead of keeping in-memory buffers, keep document - objects that already contain the parsed fragment: - </li></ul></div> -<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">append_fragment</span><span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">target</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_document</span><span class="special">&</span> <span class="identifier">cached_fragment</span><span class="special">)</span> -<span class="special">{</span> - <span class="keyword">for</span> <span class="special">(</span><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span> <span class="identifier">child</span> <span class="special">=</span> <span class="identifier">cached_fragment</span><span class="special">.</span><span class="identifier">first_child</span><span class="special">();</span> <span class="identifier">child</span><span class="special">;</span> <span class="identifier">child</span> <span class="special">=</span> <span class="identifier">child</span><span class="special">.</span><span class="identifier">next_sibling</span><span class="special">())</span> - <span class="identifier">target</span><span class="special">.</span><span class="identifier">append_copy</span><span class="special">(</span><span class="identifier">child</span><span class="special">);</span> -<span class="special">}</span> -</pre> -<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"> - Use xml_node::append_buffer directly: - </li></ul></div> -<pre class="programlisting"><span class="identifier">xml_parse_result</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">append_buffer</span><span class="special">(</span><span class="keyword">const</span> <span class="keyword">void</span><span class="special">*</span> <span class="identifier">contents</span><span class="special">,</span> <span class="identifier">size_t</span> <span class="identifier">size</span><span class="special">,</span> <span class="keyword">unsigned</span> <span class="keyword">int</span> <span class="identifier">options</span> <span class="special">=</span> <span class="identifier">parse_default</span><span class="special">,</span> <span class="identifier">xml_encoding</span> <span class="identifier">encoding</span> <span class="special">=</span> <span class="identifier">encoding_auto</span><span class="special">);</span> -</pre> -<p> - The first method is more convenient, but slower than the other two. The relative - performance of <code class="computeroutput"><span class="identifier">append_copy</span></code> - and <code class="computeroutput"><span class="identifier">append_buffer</span></code> depends - on the buffer format - usually <code class="computeroutput"><span class="identifier">append_buffer</span></code> - is faster if the buffer is in native encoding (UTF-8 or wchar_t, depending - on <code class="computeroutput"><span class="identifier">PUGIXML_WCHAR_MODE</span></code>). At - the same time it might be less efficient in terms of memory usage - the implementation - makes a copy of the provided buffer, and the copy has the same lifetime as - the document - the memory used by that copy will be reclaimed after the document - is destroyed, but no sooner. Even deleting all nodes in the document, including - the appended ones, won't reclaim the memory. - </p> -<p> - <code class="computeroutput"><span class="identifier">append_buffer</span></code> behaves in - the same way as <a class="link" href="loading.html#xml_document::load_buffer">xml_document::load_buffer</a> - - the input buffer is a byte buffer, with size in bytes; the buffer is not - modified and can be freed after the function returns. - </p> -<a name="status_append_invalid_root"></a><p> - Since <code class="computeroutput"><span class="identifier">append_buffer</span></code> needs - to append child nodes to the current node, it only works if the current node - is either document or element node. Calling <code class="computeroutput"><span class="identifier">append_buffer</span></code> - on a node with any other type results in an error with <code class="computeroutput"><span class="identifier">status_append_invalid_root</span></code> - status. - </p> -</div> -</div> -<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> -<td align="left"></td> -<td align="right"><div class="copyright-footer">Copyright © 2014 Arseny Kapoulkine<p> - Distributed under the MIT License - </p> -</div></td> -</tr></table> -<hr> -<table width="100%"><tr> -<td> -<a href="http://pugixml.org/">pugixml 1.6</a> manual | - <a href="../manual.html">Overview</a> | - <a href="install.html">Installation</a> | - Document: - <a href="dom.html">Object model</a> · <a href="loading.html">Loading</a> · <a href="access.html">Accessing</a> · <b>Modifying</b> · <a href="saving.html">Saving</a> | - <a href="xpath.html">XPath</a> | - <a href="apiref.html">API Reference</a> | - <a href="toc.html">Table of Contents</a> -</td> -<td width="*" align="right"><div class="spirit-nav"> -<a accesskey="p" href="access.html"><img src="../images/prev.png" alt="Prev"></a><a accesskey="u" href="../manual.html"><img src="../images/up.png" alt="Up"></a><a accesskey="h" href="../manual.html"><img src="../images/home.png" alt="Home"></a><a accesskey="n" href="saving.html"><img src="../images/next.png" alt="Next"></a> -</div></td> -</tr></table> -</body> -</html> |