733 lines
57 KiB
HTML
733 lines
57 KiB
HTML
<html>
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
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<title>Document object model</title>
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<link rel="stylesheet" href="../pugixml.css" type="text/css">
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<meta name="generator" content="DocBook XSL Stylesheets V1.78.1">
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<link rel="home" href="../manual.html" title="pugixml 1.5">
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<link rel="up" href="../manual.html" title="pugixml 1.5">
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<link rel="prev" href="install.html" title="Installation">
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<link rel="next" href="loading.html" title="Loading document">
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</head>
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<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
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<table width="100%"><tr>
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<td>
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<a href="http://pugixml.org/">pugixml 1.5</a> manual |
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<a href="../manual.html">Overview</a> |
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<a href="install.html">Installation</a> |
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Document:
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<b>Object model</b> · <a href="loading.html">Loading</a> · <a href="access.html">Accessing</a> · <a href="modify.html">Modifying</a> · <a href="saving.html">Saving</a> |
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<a href="xpath.html">XPath</a> |
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<a href="apiref.html">API Reference</a> |
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<a href="toc.html">Table of Contents</a>
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</td>
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<td width="*" align="right"><div class="spirit-nav">
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<a accesskey="p" href="install.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="loading.html"><img src="../images/next.png" alt="Next"></a>
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</div></td>
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</tr></table>
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<hr>
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<div class="section">
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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
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<a name="manual.dom"></a><a class="link" href="dom.html" title="Document object model"> Document object model</a>
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</h2></div></div></div>
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<div class="toc"><dl class="toc">
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<dt><span class="section"><a href="dom.html#manual.dom.tree"> Tree structure</a></span></dt>
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<dt><span class="section"><a href="dom.html#manual.dom.cpp"> C++ interface</a></span></dt>
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<dt><span class="section"><a href="dom.html#manual.dom.unicode"> Unicode interface</a></span></dt>
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<dt><span class="section"><a href="dom.html#manual.dom.thread"> Thread-safety guarantees</a></span></dt>
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<dt><span class="section"><a href="dom.html#manual.dom.exception"> Exception guarantees</a></span></dt>
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<dt><span class="section"><a href="dom.html#manual.dom.memory"> Memory management</a></span></dt>
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<dd><dl>
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<dt><span class="section"><a href="dom.html#manual.dom.memory.custom"> Custom memory allocation/deallocation
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functions</a></span></dt>
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<dt><span class="section"><a href="dom.html#manual.dom.memory.tuning"> Memory consumption tuning</a></span></dt>
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<dt><span class="section"><a href="dom.html#manual.dom.memory.internals"> Document memory management
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internals</a></span></dt>
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</dl></dd>
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</dl></div>
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<p>
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pugixml stores XML data in DOM-like way: the entire XML document (both document
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structure and element data) is stored in memory as a tree. The tree can be
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loaded from a character stream (file, string, C++ I/O stream), then traversed
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with the special API or XPath expressions. The whole tree is mutable: both
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node structure and node/attribute data can be changed at any time. Finally,
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the result of document transformations can be saved to a character stream (file,
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C++ I/O stream or custom transport).
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</p>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="manual.dom.tree"></a><a class="link" href="dom.html#manual.dom.tree" title="Tree structure"> Tree structure</a>
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</h3></div></div></div>
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<p>
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The XML document is represented with a tree data structure. The root of the
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tree is the document itself, which corresponds to C++ type <a class="link" href="dom.html#xml_document">xml_document</a>.
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Document has one or more child nodes, which correspond to C++ type <a class="link" href="dom.html#xml_node">xml_node</a>. Nodes have different types; depending
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on a type, a node can have a collection of child nodes, a collection of attributes,
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which correspond to C++ type <a class="link" href="dom.html#xml_attribute">xml_attribute</a>,
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and some additional data (i.e. name).
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</p>
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<a name="xml_node_type"></a><p>
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The tree nodes can be of one of the following types (which together form
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the enumeration <code class="computeroutput"><span class="identifier">xml_node_type</span></code>):
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</p>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
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<li class="listitem">
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Document node (<a name="node_document"></a><code class="literal">node_document</code>) - this
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is the root of the tree, which consists of several child nodes. This
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node corresponds to <a class="link" href="dom.html#xml_document">xml_document</a>
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class; note that <a class="link" href="dom.html#xml_document">xml_document</a> is
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a sub-class of <a class="link" href="dom.html#xml_node">xml_node</a>, so the entire
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node interface is also available. However, document node is special in
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several ways, which are covered below. There can be only one document
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node in the tree; document node does not have any XML representation.
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<br><br>
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</li>
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<li class="listitem">
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Element/tag node (<a name="node_element"></a><code class="literal">node_element</code>) - this
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is the most common type of node, which represents XML elements. Element
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nodes have a name, a collection of attributes and a collection of child
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nodes (both of which may be empty). The attribute is a simple name/value
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pair. The example XML representation of element nodes is as follows:
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</li>
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</ul></div>
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<pre class="programlisting"><span class="special"><</span><span class="identifier">node</span> <span class="identifier">attr</span><span class="special">=</span><span class="string">"value"</span><span class="special">><</span><span class="identifier">child</span><span class="special">/></</span><span class="identifier">node</span><span class="special">></span>
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</pre>
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<div class="blockquote"><blockquote class="blockquote"><p>
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There are two element nodes here: one has name <code class="computeroutput"><span class="string">"node"</span></code>,
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single attribute <code class="computeroutput"><span class="string">"attr"</span></code>
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and single child <code class="computeroutput"><span class="string">"child"</span></code>,
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another has name <code class="computeroutput"><span class="string">"child"</span></code>
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and does not have any attributes or child nodes.
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</p></blockquote></div>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
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Plain character data nodes (<a name="node_pcdata"></a><code class="literal">node_pcdata</code>)
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represent plain text in XML. PCDATA nodes have a value, but do not have
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a name or children/attributes. Note that <span class="bold"><strong>plain
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character data is not a part of the element node but instead has its
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own node</strong></span>; an element node can have several child PCDATA nodes.
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The example XML representation of text nodes is as follows:
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</li></ul></div>
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<pre class="programlisting"><span class="special"><</span><span class="identifier">node</span><span class="special">></span> <span class="identifier">text1</span> <span class="special"><</span><span class="identifier">child</span><span class="special">/></span> <span class="identifier">text2</span> <span class="special"></</span><span class="identifier">node</span><span class="special">></span>
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</pre>
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<div class="blockquote"><blockquote class="blockquote"><p>
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Here <code class="computeroutput"><span class="string">"node"</span></code> element
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has three children, two of which are PCDATA nodes with values <code class="computeroutput"><span class="string">" text1 "</span></code> and <code class="computeroutput"><span class="string">"
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text2 "</span></code>.
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</p></blockquote></div>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
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Character data nodes (<a name="node_cdata"></a><code class="literal">node_cdata</code>) represent
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text in XML that is quoted in a special way. CDATA nodes do not differ
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from PCDATA nodes except in XML representation - the above text example
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looks like this with CDATA:
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</li></ul></div>
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<pre class="programlisting"><span class="special"><</span><span class="identifier">node</span><span class="special">></span> <span class="special"><![</span><span class="identifier">CDATA</span><span class="special">[[</span><span class="identifier">text1</span><span class="special">]]></span> <span class="special"><</span><span class="identifier">child</span><span class="special">/></span> <span class="special"><![</span><span class="identifier">CDATA</span><span class="special">[[</span><span class="identifier">text2</span><span class="special">]]></span> <span class="special"></</span><span class="identifier">node</span><span class="special">></span>
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</pre>
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<div class="blockquote"><blockquote class="blockquote"><p>
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CDATA nodes make it easy to include non-escaped <, & and > characters
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in plain text. CDATA value can not contain the character sequence ]]>,
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since it is used to determine the end of node contents.
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</p></blockquote></div>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
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Comment nodes (<a name="node_comment"></a><code class="literal">node_comment</code>) represent
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comments in XML. Comment nodes have a value, but do not have a name or
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children/attributes. The example XML representation of a comment node
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is as follows:
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</li></ul></div>
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<pre class="programlisting"><span class="special"><!--</span> <span class="identifier">comment</span> <span class="identifier">text</span> <span class="special">--></span>
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</pre>
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<div class="blockquote"><blockquote class="blockquote"><p>
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Here the comment node has value <code class="computeroutput"><span class="string">"comment
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text"</span></code>. By default comment nodes are treated as non-essential
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part of XML markup and are not loaded during XML parsing. You can override
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this behavior with <a class="link" href="loading.html#parse_comments">parse_comments</a>
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flag.
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</p></blockquote></div>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
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Processing instruction node (<a name="node_pi"></a><code class="literal">node_pi</code>) represent
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processing instructions (PI) in XML. PI nodes have a name and an optional
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value, but do not have children/attributes. The example XML representation
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of a PI node is as follows:
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</li></ul></div>
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<pre class="programlisting"><span class="special"><?</span><span class="identifier">name</span> <span class="identifier">value</span><span class="special">?></span>
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</pre>
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<div class="blockquote"><blockquote class="blockquote"><p>
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Here the name (also called PI target) is <code class="computeroutput"><span class="string">"name"</span></code>,
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and the value is <code class="computeroutput"><span class="string">"value"</span></code>.
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By default PI nodes are treated as non-essential part of XML markup and
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are not loaded during XML parsing. You can override this behavior with
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<a class="link" href="loading.html#parse_pi">parse_pi</a> flag.
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</p></blockquote></div>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
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Declaration node (<a name="node_declaration"></a><code class="literal">node_declaration</code>)
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represents document declarations in XML. Declaration nodes have a name
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(<code class="computeroutput"><span class="string">"xml"</span></code>) and an
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optional collection of attributes, but do not have value or children.
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There can be only one declaration node in a document; moreover, it should
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be the topmost node (its parent should be the document). The example
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XML representation of a declaration node is as follows:
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</li></ul></div>
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<pre class="programlisting"><span class="special"><?</span><span class="identifier">xml</span> <span class="identifier">version</span><span class="special">=</span><span class="string">"1.0"</span><span class="special">?></span>
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</pre>
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<div class="blockquote"><blockquote class="blockquote"><p>
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Here the node has name <code class="computeroutput"><span class="string">"xml"</span></code>
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and a single attribute with name <code class="computeroutput"><span class="string">"version"</span></code>
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and value <code class="computeroutput"><span class="string">"1.0"</span></code>.
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By default declaration nodes are treated as non-essential part of XML markup
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and are not loaded during XML parsing. You can override this behavior with
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<a class="link" href="loading.html#parse_declaration">parse_declaration</a> flag. Also,
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by default a dummy declaration is output when XML document is saved unless
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there is already a declaration in the document; you can disable this with
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<a class="link" href="saving.html#format_no_declaration">format_no_declaration</a> flag.
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</p></blockquote></div>
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<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
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Document type declaration node (<a name="node_doctype"></a><code class="literal">node_doctype</code>)
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represents document type declarations in XML. Document type declaration
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nodes have a value, which corresponds to the entire document type contents;
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no additional nodes are created for inner elements like <code class="computeroutput"><span class="special"><!</span><span class="identifier">ENTITY</span><span class="special">></span></code>. There can be only one document type
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declaration node in a document; moreover, it should be the topmost node
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(its parent should be the document). The example XML representation of
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a document type declaration node is as follows:
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</li></ul></div>
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<pre class="programlisting"><span class="special"><!</span><span class="identifier">DOCTYPE</span> <span class="identifier">greeting</span> <span class="special">[</span> <span class="special"><!</span><span class="identifier">ELEMENT</span> <span class="identifier">greeting</span> <span class="special">(</span><span class="preprocessor">#PCDATA</span><span class="special">)></span> <span class="special">]></span>
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</pre>
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<div class="blockquote"><blockquote class="blockquote"><p>
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Here the node has value <code class="computeroutput"><span class="string">"greeting [ <!ELEMENT
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greeting (#PCDATA)> ]"</span></code>. By default document type
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declaration nodes are treated as non-essential part of XML markup and are
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not loaded during XML parsing. You can override this behavior with <a class="link" href="loading.html#parse_doctype">parse_doctype</a> flag.
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</p></blockquote></div>
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<p>
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Finally, here is a complete example of XML document and the corresponding
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tree representation (<a href="../samples/tree.xml" target="_top">samples/tree.xml</a>):
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</p>
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<div class="informaltable"><table class="table">
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<colgroup>
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<col>
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<col>
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</colgroup>
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<tbody><tr>
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<td>
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<p>
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</p>
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<pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="special"><?</span><span class="identifier">xml</span> <span class="identifier">version</span><span class="special">=</span><span class="string">"1.0"</span><span class="special">?></span>
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<span class="special"><</span><span class="identifier">mesh</span> <span class="identifier">name</span><span class="special">=</span><span class="string">"mesh_root"</span><span class="special">></span>
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<span class="special"><!--</span> <span class="identifier">here</span> <span class="identifier">is</span> <span class="identifier">a</span> <span class="identifier">mesh</span> <span class="identifier">node</span> <span class="special">--></span>
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<span class="identifier">some</span> <span class="identifier">text</span>
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<span class="special"><![</span><span class="identifier">CDATA</span><span class="special">[</span><span class="identifier">someothertext</span><span class="special">]]></span>
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<span class="identifier">some</span> <span class="identifier">more</span> <span class="identifier">text</span>
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<span class="special"><</span><span class="identifier">node</span> <span class="identifier">attr1</span><span class="special">=</span><span class="string">"value1"</span> <span class="identifier">attr2</span><span class="special">=</span><span class="string">"value2"</span> <span class="special">/></span>
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<span class="special"><</span><span class="identifier">node</span> <span class="identifier">attr1</span><span class="special">=</span><span class="string">"value2"</span><span class="special">></span>
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<span class="special"><</span><span class="identifier">innernode</span><span class="special">/></span>
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<span class="special"></</span><span class="identifier">node</span><span class="special">></span>
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<span class="special"></</span><span class="identifier">mesh</span><span class="special">></span>
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<span class="special"><?</span><span class="identifier">include</span> <span class="identifier">somedata</span><span class="special">?></span>
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</pre>
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<p>
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</p>
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</td>
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<td>
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<p>
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<a href="../images/dom_tree.png" target="_top"><span class="inlinemediaobject"><img src="../images/dom_tree_thumb.png" alt="dom_tree_thumb"></span></a>
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</p>
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</td>
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</tr></tbody>
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</table></div>
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</div>
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<div class="section">
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<div class="titlepage"><div><div><h3 class="title">
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|
<a name="manual.dom.cpp"></a><a class="link" href="dom.html#manual.dom.cpp" title="C++ interface"> C++ interface</a>
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</h3></div></div></div>
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<div class="note"><table border="0" summary="Note">
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<tr>
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<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../images/note.png"></td>
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<th align="left">Note</th>
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</tr>
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<tr><td align="left" valign="top"><p>
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All pugixml classes and functions are located in the <code class="computeroutput"><span class="identifier">pugi</span></code>
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namespace; you have to either use explicit name qualification (i.e. <code class="computeroutput"><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span></code>), or to gain access to relevant
|
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symbols via <code class="computeroutput"><span class="keyword">using</span></code> directive
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(i.e. <code class="computeroutput"><span class="keyword">using</span> <span class="identifier">pugi</span><span class="special">::</span><span class="identifier">xml_node</span><span class="special">;</span></code> or <code class="computeroutput"><span class="keyword">using</span>
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<span class="keyword">namespace</span> <span class="identifier">pugi</span><span class="special">;</span></code>). The namespace will be omitted from all
|
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declarations in this documentation hereafter; all code examples will use
|
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fully qualified names.
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</p></td></tr>
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</table></div>
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<p>
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Despite the fact that there are several node types, there are only three
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C++ classes representing the tree (<code class="computeroutput"><span class="identifier">xml_document</span></code>,
|
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<code class="computeroutput"><span class="identifier">xml_node</span></code>, <code class="computeroutput"><span class="identifier">xml_attribute</span></code>);
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some operations on <code class="computeroutput"><span class="identifier">xml_node</span></code>
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are only valid for certain node types. The classes are described below.
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</p>
|
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<a name="xml_document"></a><a name="xml_document::document_element"></a><p>
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<code class="computeroutput"><span class="identifier">xml_document</span></code> is the owner
|
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of the entire document structure; it is a non-copyable class. The interface
|
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of <code class="computeroutput"><span class="identifier">xml_document</span></code> consists
|
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of loading functions (see <a class="xref" href="loading.html" title="Loading document"> Loading document</a>), saving functions (see <a class="xref" href="saving.html" title="Saving document"> Saving document</a>)
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and the entire interface of <code class="computeroutput"><span class="identifier">xml_node</span></code>,
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which allows for document inspection and/or modification. Note that while
|
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<code class="computeroutput"><span class="identifier">xml_document</span></code> is a sub-class
|
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of <code class="computeroutput"><span class="identifier">xml_node</span></code>, <code class="computeroutput"><span class="identifier">xml_node</span></code> is not a polymorphic type; the
|
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inheritance is present only to simplify usage. Alternatively you can use
|
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the <code class="computeroutput"><span class="identifier">document_element</span></code> function
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to get the element node that's the immediate child of the document.
|
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</p>
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<a name="xml_document::ctor"></a><a name="xml_document::dtor"></a><a name="xml_document::reset"></a><p>
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Default constructor of <code class="computeroutput"><span class="identifier">xml_document</span></code>
|
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initializes the document to the tree with only a root node (document node).
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You can then populate it with data using either tree modification functions
|
|
or loading functions; all loading functions destroy the previous tree with
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all occupied memory, which puts existing node/attribute handles for this
|
|
document to invalid state. If you want to destroy the previous tree, you
|
|
can use the <code class="computeroutput"><span class="identifier">xml_document</span><span class="special">::</span><span class="identifier">reset</span></code>
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function; it destroys the tree and replaces it with either an empty one or
|
|
a copy of the specified document. Destructor of <code class="computeroutput"><span class="identifier">xml_document</span></code>
|
|
also destroys the tree, thus the lifetime of the document object should exceed
|
|
the lifetimes of any node/attribute handles that point to the tree.
|
|
</p>
|
|
<div class="caution"><table border="0" summary="Caution">
|
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<tr>
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<td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="../images/caution.png"></td>
|
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<th align="left">Caution</th>
|
|
</tr>
|
|
<tr><td align="left" valign="top"><p>
|
|
While technically node/attribute handles can be alive when the tree they're
|
|
referring to is destroyed, calling any member function for these handles
|
|
results in undefined behavior. Thus it is recommended to make sure that
|
|
the document is destroyed only after all references to its nodes/attributes
|
|
are destroyed.
|
|
</p></td></tr>
|
|
</table></div>
|
|
<a name="xml_node"></a><a name="xml_node::type"></a><p>
|
|
<code class="computeroutput"><span class="identifier">xml_node</span></code> is the handle to
|
|
document node; it can point to any node in the document, including the document
|
|
node itself. There is a common interface for nodes of all types; the actual
|
|
<a class="link" href="dom.html#xml_node_type">node type</a> can be queried via the <code class="computeroutput"><span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">type</span><span class="special">()</span></code>
|
|
method. Note that <code class="computeroutput"><span class="identifier">xml_node</span></code>
|
|
is only a handle to the actual node, not the node itself - you can have several
|
|
<code class="computeroutput"><span class="identifier">xml_node</span></code> handles pointing
|
|
to the same underlying object. Destroying <code class="computeroutput"><span class="identifier">xml_node</span></code>
|
|
handle does not destroy the node and does not remove it from the tree. The
|
|
size of <code class="computeroutput"><span class="identifier">xml_node</span></code> is equal
|
|
to that of a pointer, so it is nothing more than a lightweight wrapper around
|
|
a pointer; you can safely pass or return <code class="computeroutput"><span class="identifier">xml_node</span></code>
|
|
objects by value without additional overhead.
|
|
</p>
|
|
<a name="node_null"></a><p>
|
|
There is a special value of <code class="computeroutput"><span class="identifier">xml_node</span></code>
|
|
type, known as null node or empty node (such nodes have type <code class="computeroutput"><span class="identifier">node_null</span></code>). It does not correspond to any
|
|
node in any document, and thus resembles null pointer. However, all operations
|
|
are defined on empty nodes; generally the operations don't do anything and
|
|
return empty nodes/attributes or empty strings as their result (see documentation
|
|
for specific functions for more detailed information). This is useful for
|
|
chaining calls; i.e. you can get the grandparent of a node like so: <code class="computeroutput"><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>; if a node is a null node or it does not
|
|
have a parent, the first <code class="computeroutput"><span class="identifier">parent</span><span class="special">()</span></code> call returns null node; the second <code class="computeroutput"><span class="identifier">parent</span><span class="special">()</span></code>
|
|
call then also returns null node, which makes error handling easier.
|
|
</p>
|
|
<a name="xml_attribute"></a><p>
|
|
<code class="computeroutput"><span class="identifier">xml_attribute</span></code> is the handle
|
|
to an XML attribute; it has the same semantics as <code class="computeroutput"><span class="identifier">xml_node</span></code>,
|
|
i.e. there can be several <code class="computeroutput"><span class="identifier">xml_attribute</span></code>
|
|
handles pointing to the same underlying object and there is a special null
|
|
attribute value, which propagates to function results.
|
|
</p>
|
|
<a name="xml_attribute::ctor"></a><a name="xml_node::ctor"></a><p>
|
|
Both <code class="computeroutput"><span class="identifier">xml_node</span></code> and <code class="computeroutput"><span class="identifier">xml_attribute</span></code> have the default constructor
|
|
which initializes them to null objects.
|
|
</p>
|
|
<a name="xml_attribute::comparison"></a><a name="xml_node::comparison"></a><p>
|
|
<code class="computeroutput"><span class="identifier">xml_node</span></code> and <code class="computeroutput"><span class="identifier">xml_attribute</span></code> try to behave like pointers,
|
|
that is, they can be compared with other objects of the same type, making
|
|
it possible to use them as keys in associative containers. All handles to
|
|
the same underlying object are equal, and any two handles to different underlying
|
|
objects are not equal. Null handles only compare as equal to themselves.
|
|
The result of relational comparison can not be reliably determined from the
|
|
order of nodes in file or in any other way. Do not use relational comparison
|
|
operators except for search optimization (i.e. associative container keys).
|
|
</p>
|
|
<a name="xml_attribute::hash_value"></a><a name="xml_node::hash_value"></a><p>
|
|
If you want to use <code class="computeroutput"><span class="identifier">xml_node</span></code>
|
|
or <code class="computeroutput"><span class="identifier">xml_attribute</span></code> objects
|
|
as keys in hash-based associative containers, you can use the <code class="computeroutput"><span class="identifier">hash_value</span></code> member functions. They return
|
|
the hash values that are guaranteed to be the same for all handles to the
|
|
same underlying object. The hash value for null handles is 0.
|
|
</p>
|
|
<a name="xml_attribute::unspecified_bool_type"></a><a name="xml_node::unspecified_bool_type"></a><a name="xml_attribute::empty"></a><a name="xml_node::empty"></a><p>
|
|
Finally handles can be implicitly cast to boolean-like objects, so that you
|
|
can test if the node/attribute is empty with the following code: <code class="computeroutput"><span class="keyword">if</span> <span class="special">(</span><span class="identifier">node</span><span class="special">)</span> <span class="special">{</span> <span class="special">...</span>
|
|
<span class="special">}</span></code> or <code class="computeroutput"><span class="keyword">if</span>
|
|
<span class="special">(!</span><span class="identifier">node</span><span class="special">)</span> <span class="special">{</span> <span class="special">...</span>
|
|
<span class="special">}</span> <span class="keyword">else</span> <span class="special">{</span> <span class="special">...</span> <span class="special">}</span></code>.
|
|
Alternatively you can check if a given <code class="computeroutput"><span class="identifier">xml_node</span></code>/<code class="computeroutput"><span class="identifier">xml_attribute</span></code> handle is null by calling
|
|
the following methods:
|
|
</p>
|
|
<pre class="programlisting"><span class="keyword">bool</span> <span class="identifier">xml_attribute</span><span class="special">::</span><span class="identifier">empty</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>
|
|
<span class="keyword">bool</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">empty</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>
|
|
</pre>
|
|
<p>
|
|
Nodes and attributes do not exist without a document tree, so you can't create
|
|
them without adding them to some document. Once underlying node/attribute
|
|
objects are destroyed, the handles to those objects become invalid. While
|
|
this means that destruction of the entire tree invalidates all node/attribute
|
|
handles, it also means that destroying a subtree (by calling <a class="link" href="modify.html#xml_node::remove_child">xml_node::remove_child</a>)
|
|
or removing an attribute invalidates the corresponding handles. There is
|
|
no way to check handle validity; you have to ensure correctness through external
|
|
mechanisms.
|
|
</p>
|
|
</div>
|
|
<div class="section">
|
|
<div class="titlepage"><div><div><h3 class="title">
|
|
<a name="manual.dom.unicode"></a><a class="link" href="dom.html#manual.dom.unicode" title="Unicode interface"> Unicode interface</a>
|
|
</h3></div></div></div>
|
|
<p>
|
|
There are two choices of interface and internal representation when configuring
|
|
pugixml: you can either choose the UTF-8 (also called char) interface or
|
|
UTF-16/32 (also called wchar_t) one. The choice is controlled via <a class="link" href="install.html#PUGIXML_WCHAR_MODE">PUGIXML_WCHAR_MODE</a>
|
|
define; you can set it via <code class="filename">pugiconfig.hpp</code> or via preprocessor options, as
|
|
discussed in <a class="xref" href="install.html#manual.install.building.config" title="Additional configuration options"> Additional configuration
|
|
options</a>. If this define is set, the wchar_t
|
|
interface is used; otherwise (by default) the char interface is used. The
|
|
exact wide character encoding is assumed to be either UTF-16 or UTF-32 and
|
|
is determined based on the size of <code class="computeroutput"><span class="keyword">wchar_t</span></code>
|
|
type.
|
|
</p>
|
|
<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>
|
|
If the size of <code class="computeroutput"><span class="keyword">wchar_t</span></code> is
|
|
2, pugixml assumes UTF-16 encoding instead of UCS-2, which means that some
|
|
characters are represented as two code points.
|
|
</p></td></tr>
|
|
</table></div>
|
|
<p>
|
|
All tree functions that work with strings work with either C-style null terminated
|
|
strings or STL strings of the selected character type. For example, node
|
|
name accessors look like this in char mode:
|
|
</p>
|
|
<pre class="programlisting"><span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">name</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>
|
|
<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="keyword">char</span><span class="special">*</span> <span class="identifier">value</span><span class="special">);</span>
|
|
</pre>
|
|
<p>
|
|
and like this in wchar_t mode:
|
|
</p>
|
|
<pre class="programlisting"><span class="keyword">const</span> <span class="keyword">wchar_t</span><span class="special">*</span> <span class="identifier">xml_node</span><span class="special">::</span><span class="identifier">name</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span>
|
|
<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="keyword">wchar_t</span><span class="special">*</span> <span class="identifier">value</span><span class="special">);</span>
|
|
</pre>
|
|
<a name="char_t"></a><a name="string_t"></a><p>
|
|
There is a special type, <code class="computeroutput"><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">char_t</span></code>,
|
|
that is defined as the character type and depends on the library configuration;
|
|
it will be also used in the documentation hereafter. There is also a type
|
|
<code class="computeroutput"><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">string_t</span></code>, which is defined as the STL string
|
|
of the character type; it corresponds to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>
|
|
in char mode and to <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">wstring</span></code> in wchar_t mode.
|
|
</p>
|
|
<p>
|
|
In addition to the interface, the internal implementation changes to store
|
|
XML data as <code class="computeroutput"><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">char_t</span></code>; this means that these two modes
|
|
have different memory usage characteristics. The conversion to <code class="computeroutput"><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">char_t</span></code> upon document loading and from
|
|
<code class="computeroutput"><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">char_t</span></code> upon document saving happen automatically,
|
|
which also carries minor performance penalty. The general advice however
|
|
is to select the character mode based on usage scenario, i.e. if UTF-8 is
|
|
inconvenient to process and most of your XML data is non-ASCII, wchar_t mode
|
|
is probably a better choice.
|
|
</p>
|
|
<a name="as_utf8"></a><a name="as_wide"></a><p>
|
|
There are cases when you'll have to convert string data between UTF-8 and
|
|
wchar_t encodings; the following helper functions are provided for such purposes:
|
|
</p>
|
|
<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">as_utf8</span><span class="special">(</span><span class="keyword">const</span> <span class="keyword">wchar_t</span><span class="special">*</span> <span class="identifier">str</span><span class="special">);</span>
|
|
<span class="identifier">std</span><span class="special">::</span><span class="identifier">wstring</span> <span class="identifier">as_wide</span><span class="special">(</span><span class="keyword">const</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">str</span><span class="special">);</span>
|
|
</pre>
|
|
<p>
|
|
Both functions accept a null-terminated string as an argument <code class="computeroutput"><span class="identifier">str</span></code>, and return the converted string.
|
|
<code class="computeroutput"><span class="identifier">as_utf8</span></code> performs conversion
|
|
from UTF-16/32 to UTF-8; <code class="computeroutput"><span class="identifier">as_wide</span></code>
|
|
performs conversion from UTF-8 to UTF-16/32. Invalid UTF sequences are silently
|
|
discarded upon conversion. <code class="computeroutput"><span class="identifier">str</span></code>
|
|
has to be a valid string; passing null pointer results in undefined behavior.
|
|
There are also two overloads with the same semantics which accept a string
|
|
as an argument:
|
|
</p>
|
|
<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">as_utf8</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">wstring</span><span class="special">&</span> <span class="identifier">str</span><span class="special">);</span>
|
|
<span class="identifier">std</span><span class="special">::</span><span class="identifier">wstring</span> <span class="identifier">as_wide</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&</span> <span class="identifier">str</span><span class="special">);</span>
|
|
</pre>
|
|
<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>
|
|
Most examples in this documentation assume char interface and therefore
|
|
will not compile with <a class="link" href="install.html#PUGIXML_WCHAR_MODE">PUGIXML_WCHAR_MODE</a>.
|
|
This is done to simplify the documentation; usually the only changes you'll
|
|
have to make is to pass <code class="computeroutput"><span class="keyword">wchar_t</span></code>
|
|
string literals, i.e. instead of
|
|
</p>
|
|
<p>
|
|
<code class="computeroutput"><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">"bookstore"</span><span class="special">).</span><span class="identifier">find_child_by_attribute</span><span class="special">(</span><span class="string">"book"</span><span class="special">,</span> <span class="string">"id"</span><span class="special">,</span> <span class="string">"12345"</span><span class="special">);</span></code>
|
|
</p>
|
|
<p>
|
|
you'll have to do
|
|
</p>
|
|
<p>
|
|
<code class="computeroutput"><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="identifier">L</span><span class="string">"bookstore"</span><span class="special">).</span><span class="identifier">find_child_by_attribute</span><span class="special">(</span><span class="identifier">L</span><span class="string">"book"</span><span class="special">,</span> <span class="identifier">L</span><span class="string">"id"</span><span class="special">,</span> <span class="identifier">L</span><span class="string">"12345"</span><span class="special">);</span></code>
|
|
</p>
|
|
</td></tr>
|
|
</table></div>
|
|
</div>
|
|
<div class="section">
|
|
<div class="titlepage"><div><div><h3 class="title">
|
|
<a name="manual.dom.thread"></a><a class="link" href="dom.html#manual.dom.thread" title="Thread-safety guarantees"> Thread-safety guarantees</a>
|
|
</h3></div></div></div>
|
|
<p>
|
|
Almost all functions in pugixml have the following thread-safety guarantees:
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
it is safe to call free (non-member) functions from multiple threads
|
|
</li>
|
|
<li class="listitem">
|
|
it is safe to perform concurrent read-only accesses to the same tree
|
|
(all constant member functions do not modify the tree)
|
|
</li>
|
|
<li class="listitem">
|
|
it is safe to perform concurrent read/write accesses, if there is only
|
|
one read or write access to the single tree at a time
|
|
</li>
|
|
</ul></div>
|
|
<p>
|
|
Concurrent modification and traversing of a single tree requires synchronization,
|
|
for example via reader-writer lock. Modification includes altering document
|
|
structure and altering individual node/attribute data, i.e. changing names/values.
|
|
</p>
|
|
<p>
|
|
The only exception is <a class="link" href="dom.html#set_memory_management_functions">set_memory_management_functions</a>;
|
|
it modifies global variables and as such is not thread-safe. Its usage policy
|
|
has more restrictions, see <a class="xref" href="dom.html#manual.dom.memory.custom" title="Custom memory allocation/deallocation functions"> Custom memory allocation/deallocation
|
|
functions</a>.
|
|
</p>
|
|
</div>
|
|
<div class="section">
|
|
<div class="titlepage"><div><div><h3 class="title">
|
|
<a name="manual.dom.exception"></a><a class="link" href="dom.html#manual.dom.exception" title="Exception guarantees"> Exception guarantees</a>
|
|
</h3></div></div></div>
|
|
<p>
|
|
With the exception of XPath, pugixml itself does not throw any exceptions.
|
|
Additionally, most pugixml functions have a no-throw exception guarantee.
|
|
</p>
|
|
<p>
|
|
This is not applicable to functions that operate on STL strings or IOstreams;
|
|
such functions have either strong guarantee (functions that operate on strings)
|
|
or basic guarantee (functions that operate on streams). Also functions that
|
|
call user-defined callbacks (i.e. <a class="link" href="access.html#xml_node::traverse">xml_node::traverse</a>
|
|
or <a class="link" href="access.html#xml_node::find_node">xml_node::find_node</a>) do not
|
|
provide any exception guarantees beyond the ones provided by the callback.
|
|
</p>
|
|
<p>
|
|
If exception handling is not disabled with <a class="link" href="install.html#PUGIXML_NO_EXCEPTIONS">PUGIXML_NO_EXCEPTIONS</a>
|
|
define, XPath functions may throw <a class="link" href="xpath.html#xpath_exception">xpath_exception</a>
|
|
on parsing errors; also, XPath functions may throw <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">bad_alloc</span></code>
|
|
in low memory conditions. Still, XPath functions provide strong exception
|
|
guarantee.
|
|
</p>
|
|
</div>
|
|
<div class="section">
|
|
<div class="titlepage"><div><div><h3 class="title">
|
|
<a name="manual.dom.memory"></a><a class="link" href="dom.html#manual.dom.memory" title="Memory management"> Memory management</a>
|
|
</h3></div></div></div>
|
|
<p>
|
|
pugixml requests the memory needed for document storage in big chunks, and
|
|
allocates document data inside those chunks. This section discusses replacing
|
|
functions used for chunk allocation and internal memory management implementation.
|
|
</p>
|
|
<div class="section">
|
|
<div class="titlepage"><div><div><h4 class="title">
|
|
<a name="manual.dom.memory.custom"></a><a class="link" href="dom.html#manual.dom.memory.custom" title="Custom memory allocation/deallocation functions"> Custom memory allocation/deallocation
|
|
functions</a>
|
|
</h4></div></div></div>
|
|
<a name="allocation_function"></a><a name="deallocation_function"></a><p>
|
|
All memory for tree structure, tree data and XPath objects is allocated
|
|
via globally specified functions, which default to malloc/free. You can
|
|
set your own allocation functions with set_memory_management function.
|
|
The function interfaces are the same as that of malloc/free:
|
|
</p>
|
|
<pre class="programlisting"><span class="keyword">typedef</span> <span class="keyword">void</span><span class="special">*</span> <span class="special">(*</span><span class="identifier">allocation_function</span><span class="special">)(</span><span class="identifier">size_t</span> <span class="identifier">size</span><span class="special">);</span>
|
|
<span class="keyword">typedef</span> <span class="keyword">void</span> <span class="special">(*</span><span class="identifier">deallocation_function</span><span class="special">)(</span><span class="keyword">void</span><span class="special">*</span> <span class="identifier">ptr</span><span class="special">);</span>
|
|
</pre>
|
|
<a name="set_memory_management_functions"></a><a name="get_memory_allocation_function"></a><a name="get_memory_deallocation_function"></a><p>
|
|
You can use the following accessor functions to change or get current memory
|
|
management functions:
|
|
</p>
|
|
<pre class="programlisting"><span class="keyword">void</span> <span class="identifier">set_memory_management_functions</span><span class="special">(</span><span class="identifier">allocation_function</span> <span class="identifier">allocate</span><span class="special">,</span> <span class="identifier">deallocation_function</span> <span class="identifier">deallocate</span><span class="special">);</span>
|
|
<span class="identifier">allocation_function</span> <span class="identifier">get_memory_allocation_function</span><span class="special">();</span>
|
|
<span class="identifier">deallocation_function</span> <span class="identifier">get_memory_deallocation_function</span><span class="special">();</span>
|
|
</pre>
|
|
<p>
|
|
Allocation function is called with the size (in bytes) as an argument and
|
|
should return a pointer to a memory block with alignment that is suitable
|
|
for storage of primitive types (usually a maximum of <code class="computeroutput"><span class="keyword">void</span><span class="special">*</span></code> and <code class="computeroutput"><span class="keyword">double</span></code>
|
|
types alignment is sufficient) and size that is greater than or equal to
|
|
the requested one. If the allocation fails, the function has to return
|
|
null pointer (throwing an exception from allocation function results in
|
|
undefined behavior).
|
|
</p>
|
|
<p>
|
|
Deallocation function is called with the pointer that was returned by some
|
|
call to allocation function; it is never called with a null pointer. If
|
|
memory management functions are not thread-safe, library thread safety
|
|
is not guaranteed.
|
|
</p>
|
|
<p>
|
|
This is a simple example of custom memory management (<a href="../samples/custom_memory_management.cpp" target="_top">samples/custom_memory_management.cpp</a>):
|
|
</p>
|
|
<p>
|
|
|
|
</p>
|
|
<pre class="programlisting"><span class="keyword">void</span><span class="special">*</span> <span class="identifier">custom_allocate</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="keyword">return</span> <span class="keyword">new</span> <span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">nothrow</span><span class="special">)</span> <span class="keyword">char</span><span class="special">[</span><span class="identifier">size</span><span class="special">];</span>
|
|
<span class="special">}</span>
|
|
|
|
<span class="keyword">void</span> <span class="identifier">custom_deallocate</span><span class="special">(</span><span class="keyword">void</span><span class="special">*</span> <span class="identifier">ptr</span><span class="special">)</span>
|
|
<span class="special">{</span>
|
|
<span class="keyword">delete</span><span class="special">[]</span> <span class="keyword">static_cast</span><span class="special"><</span><span class="keyword">char</span><span class="special">*>(</span><span class="identifier">ptr</span><span class="special">);</span>
|
|
<span class="special">}</span>
|
|
</pre>
|
|
<p>
|
|
</p>
|
|
<p>
|
|
|
|
</p>
|
|
<pre class="programlisting"><span class="identifier">pugi</span><span class="special">::</span><span class="identifier">set_memory_management_functions</span><span class="special">(</span><span class="identifier">custom_allocate</span><span class="special">,</span> <span class="identifier">custom_deallocate</span><span class="special">);</span>
|
|
</pre>
|
|
<p>
|
|
</p>
|
|
<p>
|
|
When setting new memory management functions, care must be taken to make
|
|
sure that there are no live pugixml objects. Otherwise when the objects
|
|
are destroyed, the new deallocation function will be called with the memory
|
|
obtained by the old allocation function, resulting in undefined behavior.
|
|
</p>
|
|
</div>
|
|
<div class="section">
|
|
<div class="titlepage"><div><div><h4 class="title">
|
|
<a name="manual.dom.memory.tuning"></a><a class="link" href="dom.html#manual.dom.memory.tuning" title="Memory consumption tuning"> Memory consumption tuning</a>
|
|
</h4></div></div></div>
|
|
<p>
|
|
There are several important buffering optimizations in pugixml that rely
|
|
on predefined constants. These constants have default values that were
|
|
tuned for common usage patterns; for some applications, changing these
|
|
constants might improve memory consumption or increase performance. Changing
|
|
these constants is not recommended unless their default values result in
|
|
visible problems.
|
|
</p>
|
|
<p>
|
|
These constants can be tuned via configuration defines, as discussed in
|
|
<a class="xref" href="install.html#manual.install.building.config" title="Additional configuration options"> Additional configuration
|
|
options</a>; it is recommended to set them in <code class="filename">pugiconfig.hpp</code>.
|
|
</p>
|
|
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
|
|
<li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">PUGIXML_MEMORY_PAGE_SIZE</span></code>
|
|
controls the page size for document memory allocation. Memory for node/attribute
|
|
objects is allocated in pages of the specified size. The default size
|
|
is 32 Kb; for some applications the size is too large (i.e. embedded
|
|
systems with little heap space or applications that keep lots of XML
|
|
documents in memory). A minimum size of 1 Kb is recommended. <br><br>
|
|
|
|
</li>
|
|
<li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">PUGIXML_MEMORY_OUTPUT_STACK</span></code>
|
|
controls the cumulative stack space required to output the node. Any
|
|
output operation (i.e. saving a subtree to file) uses an internal buffering
|
|
scheme for performance reasons. The default size is 10 Kb; if you're
|
|
using node output from threads with little stack space, decreasing
|
|
this value can prevent stack overflows. A minimum size of 1 Kb is recommended.
|
|
<br><br>
|
|
|
|
</li>
|
|
<li class="listitem">
|
|
<code class="computeroutput"><span class="identifier">PUGIXML_MEMORY_XPATH_PAGE_SIZE</span></code>
|
|
controls the page size for XPath memory allocation. Memory for XPath
|
|
query objects as well as internal memory for XPath evaluation is allocated
|
|
in pages of the specified size. The default size is 4 Kb; if you have
|
|
a lot of resident XPath query objects, you might need to decrease the
|
|
size to improve memory consumption. A minimum size of 256 bytes is
|
|
recommended.
|
|
</li>
|
|
</ul></div>
|
|
</div>
|
|
<div class="section">
|
|
<div class="titlepage"><div><div><h4 class="title">
|
|
<a name="manual.dom.memory.internals"></a><a class="link" href="dom.html#manual.dom.memory.internals" title="Document memory management internals"> Document memory management
|
|
internals</a>
|
|
</h4></div></div></div>
|
|
<p>
|
|
Constructing a document object using the default constructor does not result
|
|
in any allocations; document node is stored inside the <a class="link" href="dom.html#xml_document">xml_document</a>
|
|
object.
|
|
</p>
|
|
<p>
|
|
When the document is loaded from file/buffer, unless an inplace loading
|
|
function is used (see <a class="xref" href="loading.html#manual.loading.memory" title="Loading document from memory"> Loading document from memory</a>), a complete copy of character
|
|
stream is made; all names/values of nodes and attributes are allocated
|
|
in this buffer. This buffer is allocated via a single large allocation
|
|
and is only freed when document memory is reclaimed (i.e. if the <a class="link" href="dom.html#xml_document">xml_document</a> object is destroyed or if another
|
|
document is loaded in the same object). Also when loading from file or
|
|
stream, an additional large allocation may be performed if encoding conversion
|
|
is required; a temporary buffer is allocated, and it is freed before load
|
|
function returns.
|
|
</p>
|
|
<p>
|
|
All additional memory, such as memory for document structure (node/attribute
|
|
objects) and memory for node/attribute names/values is allocated in pages
|
|
on the order of 32 kilobytes; actual objects are allocated inside the pages
|
|
using a memory management scheme optimized for fast allocation/deallocation
|
|
of many small objects. Because of the scheme specifics, the pages are only
|
|
destroyed if all objects inside them are destroyed; also, generally destroying
|
|
an object does not mean that subsequent object creation will reuse the
|
|
same memory. This means that it is possible to devise a usage scheme which
|
|
will lead to higher memory usage than expected; one example is adding a
|
|
lot of nodes, and them removing all even numbered ones; not a single page
|
|
is reclaimed in the process. However this is an example specifically crafted
|
|
to produce unsatisfying behavior; in all practical usage scenarios the
|
|
memory consumption is less than that of a general-purpose allocator because
|
|
allocation meta-data is very small in size.
|
|
</p>
|
|
</div>
|
|
</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 1.5</a> manual |
|
|
<a href="../manual.html">Overview</a> |
|
|
<a href="install.html">Installation</a> |
|
|
Document:
|
|
<b>Object model</b> · <a href="loading.html">Loading</a> · <a href="access.html">Accessing</a> · <a href="modify.html">Modifying</a> · <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="install.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="loading.html"><img src="../images/next.png" alt="Next"></a>
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