libxml-xpath.html

xml开源解析代码.版本为libxml2-2.6.29,可支持GB3212.网络消息发送XML时很有用.

    <a name="XPATH_NUMBER" id="XPATH_NUMBER">XPATH_NUMBER</a> = 3
    <a name="XPATH_STRING" id="XPATH_STRING">XPATH_STRING</a> = 4
    <a name="XPATH_POINT" id="XPATH_POINT">XPATH_POINT</a> = 5
    <a name="XPATH_RANGE" id="XPATH_RANGE">XPATH_RANGE</a> = 6
    <a name="XPATH_LOCATIONSET" id="XPATH_LOCATIONSET">XPATH_LOCATIONSET</a> = 7
    <a name="XPATH_USERS" id="XPATH_USERS">XPATH_USERS</a> = 8
    <a name="XPATH_XSLT_TREE" id="XPATH_XSLT_TREE">XPATH_XSLT_TREE</a> = 9 : An XSLT value tree, non modifiable
}
</pre><h3><a name="xmlXPathParserContext" id="xmlXPathParserContext">Structure xmlXPathParserContext</a></h3><pre class="programlisting">Structure xmlXPathParserContext<br />struct _xmlXPathParserContext {
    const <a href="libxml-xmlstring.html#xmlChar">xmlChar</a> *	cur	: the current char being parsed
    const <a href="libxml-xmlstring.html#xmlChar">xmlChar</a> *	base	: the full expression
    int	error	: error code
    <a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a>	context	: the evaluation context
    <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a>	value	: the current value
    int	valueNr	: number of values stacked
    int	valueMax	: max number of values stacked
    <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> *	valueTab	: stack of values
    <a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a>	comp	: the precompiled expression
    int	xptr	: it this an XPointer expression
    <a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a>	ancestor	: used for walking preceding axis
}</pre><h3><a name="xmlXPathType" id="xmlXPathType">Structure xmlXPathType</a></h3><pre class="programlisting">Structure xmlXPathType<br />struct _xmlXPathType {
    const <a href="libxml-xmlstring.html#xmlChar">xmlChar</a> *	name	: the type name
    <a href="libxml-xpath.html#xmlXPathConvertFunc">xmlXPathConvertFunc</a>	func	: the conversion function
}</pre><h3><a name="xmlXPathVariable" id="xmlXPathVariable">Structure xmlXPathVariable</a></h3><pre class="programlisting">Structure xmlXPathVariable<br />struct _xmlXPathVariable {
    const <a href="libxml-xmlstring.html#xmlChar">xmlChar</a> *	name	: the variable name
    <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a>	value	: the value
}</pre><h3><a name="xmlXPathAxisFunc" id="xmlXPathAxisFunc"></a>Function type: xmlXPathAxisFunc</h3><pre class="programlisting">Function type: xmlXPathAxisFunc
<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a>	xmlXPathAxisFunc	(<a href="libxml-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt, <br />						 <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> cur)
</pre><p>An axis traversal function. To traverse an axis, the engine calls the first time with cur == NULL and repeat until the function returns NULL indicating the end of the axis traversal.</p><div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>the XPath interpreter context</td></tr><tr><td><span class="term"><i><tt>cur</tt></i>:</span></td><td>the previous node being explored on that axis</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the next node in that axis or NULL if at the end of the axis.</td></tr></tbody></table></div><br />
<h3><a name="xmlXPathCastBooleanToNumber" id="xmlXPathCastBooleanToNumber"></a>Function: xmlXPathCastBooleanToNumber</h3><pre class="programlisting">double	xmlXPathCastBooleanToNumber	(int val)<br />
</pre><p>Converts a boolean to its number value</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a boolean</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number value</td></tr></tbody></table></div><h3><a name="xmlXPathCastBooleanToString" id="xmlXPathCastBooleanToString"></a>Function: xmlXPathCastBooleanToString</h3><pre class="programlisting"><a href="libxml-xmlstring.html#xmlChar">xmlChar</a> *	xmlXPathCastBooleanToString	(int val)<br />
</pre><p>Converts a boolean to its string value.</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a boolean</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>a newly allocated string.</td></tr></tbody></table></div><h3><a name="xmlXPathCastNodeSetToBoolean" id="xmlXPathCastNodeSetToBoolean"></a>Function: xmlXPathCastNodeSetToBoolean</h3><pre class="programlisting">int	xmlXPathCastNodeSetToBoolean	(<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns)<br />
</pre><p>Converts a node-set to its boolean value</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>a node-set</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the boolean value</td></tr></tbody></table></div><h3><a name="xmlXPathCastNodeSetToNumber" id="xmlXPathCastNodeSetToNumber"></a>Function: xmlXPathCastNodeSetToNumber</h3><pre class="programlisting">double	xmlXPathCastNodeSetToNumber	(<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns)<br />
</pre><p>Converts a node-set to its number value</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>a node-set</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number value</td></tr></tbody></table></div><h3><a name="xmlXPathCastNodeSetToString" id="xmlXPathCastNodeSetToString"></a>Function: xmlXPathCastNodeSetToString</h3><pre class="programlisting"><a href="libxml-xmlstring.html#xmlChar">xmlChar</a> *	xmlXPathCastNodeSetToString	(<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns)<br />
</pre><p>Converts a node-set to its string value.</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>a node-set</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>a newly allocated string.</td></tr></tbody></table></div><h3><a name="xmlXPathCastNodeToNumber" id="xmlXPathCastNodeToNumber"></a>Function: xmlXPathCastNodeToNumber</h3><pre class="programlisting">double	xmlXPathCastNodeToNumber	(<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node)<br />
</pre><p>Converts a node to its number value</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>node</tt></i>:</span></td><td>a node</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number value</td></tr></tbody></table></div><h3><a name="xmlXPathCastNodeToString" id="xmlXPathCastNodeToString"></a>Function: xmlXPathCastNodeToString</h3><pre class="programlisting"><a href="libxml-xmlstring.html#xmlChar">xmlChar</a> *	xmlXPathCastNodeToString	(<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node)<br />
</pre><p>Converts a node to its string value.</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>node</tt></i>:</span></td><td>a node</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>a newly allocated string.</td></tr></tbody></table></div><h3><a name="xmlXPathCastNumberToBoolean" id="xmlXPathCastNumberToBoolean"></a>Function: xmlXPathCastNumberToBoolean</h3><pre class="programlisting">int	xmlXPathCastNumberToBoolean	(double val)<br />
</pre><p>Converts a number to its boolean value</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a number</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the boolean value</td></tr></tbody></table></div><h3><a name="xmlXPathCastNumberToString" id="xmlXPathCastNumberToString"></a>Function: xmlXPathCastNumberToString</h3><pre class="programlisting"><a href="libxml-xmlstring.html#xmlChar">xmlChar</a> *	xmlXPathCastNumberToString	(double val)<br />
</pre><p>Converts a number to its string value.</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a number</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>a newly allocated string.</td></tr></tbody></table></div><h3><a name="xmlXPathCastStringToBoolean" id="xmlXPathCastStringToBoolean"></a>Function: xmlXPathCastStringToBoolean</h3><pre class="programlisting">int	xmlXPathCastStringToBoolean	(const <a href="libxml-xmlstring.html#xmlChar">xmlChar</a> * val)<br />
</pre><p>Converts a string to its boolean value</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a string</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the boolean value</td></tr></tbody></table></div><h3><a name="xmlXPathCastStringToNumber" id="xmlXPathCastStringToNumber"></a>Function: xmlXPathCastStringToNumber</h3><pre class="programlisting">double	xmlXPathCastStringToNumber	(const <a href="libxml-xmlstring.html#xmlChar">xmlChar</a> * val)<br />
</pre><p>Converts a string to its number value</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a string</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number value</td></tr></tbody></table></div><h3><a name="xmlXPathCastToBoolean" id="xmlXPathCastToBoolean"></a>Function: xmlXPathCastToBoolean</h3><pre class="programlisting">int	xmlXPathCastToBoolean		(<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val)<br />
</pre><p>Converts an XPath object to its boolean value</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>an XPath object</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the boolean value</td></tr></tbody></table></div><h3><a name="xmlXPathCastToNumber" id="xmlXPathCastToNumber"></a>Function: xmlXPathCastToNumber</h3><pre class="programlisting">double	xmlXPathCastToNumber		(<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val)<br />
</pre><p>Converts an XPath object to its number value</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>an XPath object</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number value</td></tr></tbody></table></div><h3><a name="xmlXPathCastToString" id="xmlXPathCastToString"></a>Function: xmlXPathCastToString</h3><pre class="programlisting"><a href="libxml-xmlstring.html#xmlChar">xmlChar</a> *	xmlXPathCastToString	(<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val)<br />
</pre><p>Converts an existing object to its string() equivalent</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>an XPath object</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the allocated string value of the object, NULL in case of error. It's up to the caller to free the string memory with xmlFree().</td></tr></tbody></table></div><h3><a name="xmlXPathCmpNodes" id="xmlXPathCmpNodes"></a>Function: xmlXPathCmpNodes</h3><pre class="programlisting">int	xmlXPathCmpNodes		(<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node1, <br />					 <a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node2)<br />
</pre><p>Compare two nodes w.r.t document order</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>node1</tt></i>:</span></td><td>the first node</td></tr><tr><td><span class="term"><i><tt>node2</tt></i>:</span></td><td>the second node</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>-2 in case of error 1 if first point &lt; second point, 0 if it's the same node, -1 otherwise</td></tr></tbody></table></div><h3><a name="xmlXPathCompile" id="xmlXPathCompile"></a>Function: xmlXPathCompile</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a>	xmlXPathCompile	(const <a href="libxml-xmlstring.html#xmlChar">xmlChar</a> * str)<br />
</pre><p>Compile an XPath expression</p>
<div class="variablelist"><table border="0"><col align="left" /><tbody><tr><td><span class="term"><i><tt>str</tt></i>:</span></td><td>the XPath expression</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the <a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> resulting from the compilation or NULL. the caller has to free the object.</td></tr></tbody></table></div><h3><a name="xmlXPathCompiledEval" id="xmlXPathCompiledEval"></a>Function: xmlXPathCompiledEval</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a>	xmlXPathCompiledEval	(<a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp, <br />						 <a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctx)<br />