MTK++ Latest version: 0.2.0

Public Member Functions | Private Attributes
TiXmlHandle Class Reference

#include <mtkpp/src/tinyxml/tinyxml.h>

Collaboration diagram for TiXmlHandle:
Collaboration graph
[legend]

List of all members.

Public Member Functions

 TiXmlHandle (TiXmlNode *_node)
 Create a handle from any node (at any depth of the tree.) This can be a null pointer.
 TiXmlHandle (const TiXmlHandle &ref)
 Copy constructor.
TiXmlHandle operator= (const TiXmlHandle &ref)
TiXmlHandle FirstChild () const
 Return a handle to the first child node.
TiXmlHandle FirstChild (const char *value) const
 Return a handle to the first child node with the given name.
TiXmlHandle FirstChildElement () const
 Return a handle to the first child element.
TiXmlHandle FirstChildElement (const char *value) const
 Return a handle to the first child element with the given name.
TiXmlHandle Child (const char *value, int index) const
TiXmlHandle Child (int index) const
TiXmlHandle ChildElement (const char *value, int index) const
TiXmlHandle ChildElement (int index) const
TiXmlNodeToNode () const
TiXmlElementToElement () const
TiXmlTextToText () const
TiXmlUnknownToUnknown () const
TiXmlNodeNode () const
TiXmlElementElement () const
TiXmlTextText () const
TiXmlUnknownUnknown () const

Private Attributes

TiXmlNodenode

Detailed Description

A TiXmlHandle is a class that wraps a node pointer with null checks; this is an incredibly useful thing. Note that TiXmlHandle is not part of the TinyXml DOM structure. It is a separate utility class.

Take an example:

	<Document>
		<Element attributeA = "valueA">
			<Child attributeB = "value1" />
			<Child attributeB = "value2" />
		</Element>
	<Document>
	

Assuming you want the value of "attributeB" in the 2nd "Child" element, it's very easy to write a *lot* of code that looks like:

	TiXmlElement* root = document.FirstChildElement( "Document" );
	if ( root )
	{
		TiXmlElement* element = root->FirstChildElement( "Element" );
		if ( element )
		{
			TiXmlElement* child = element->FirstChildElement( "Child" );
			if ( child )
			{
				TiXmlElement* child2 = child->NextSiblingElement( "Child" );
				if ( child2 )
				{
					// Finally do something useful.
	

And that doesn't even cover "else" cases. TiXmlHandle addresses the verbosity of such code. A TiXmlHandle checks for null pointers so it is perfectly safe and correct to use:

	TiXmlHandle docHandle( &document );
	TiXmlElement* child2 = docHandle.FirstChild( "Document" ).FirstChild( "Element" ).Child( "Child", 1 ).ToElement();
	if ( child2 )
	{
		// do something useful
	

Which is MUCH more concise and useful.

It is also safe to copy handles - internally they are nothing more than node pointers.

	TiXmlHandle handleCopy = handle;
	

What they should not be used for is iteration:

	int i=0; 
	while ( true )
	{
		TiXmlElement* child = docHandle.FirstChild( "Document" ).FirstChild( "Element" ).Child( "Child", i ).ToElement();
		if ( !child )
			break;
		// do something
		++i;
	}
	

It seems reasonable, but it is in fact two embedded while loops. The Child method is a linear walk to find the element, so this code would iterate much more than it needs to. Instead, prefer:

	TiXmlElement* child = docHandle.FirstChild( "Document" ).FirstChild( "Element" ).FirstChild( "Child" ).ToElement();

	for( child; child; child=child->NextSiblingElement() )
	{
		// do something
	}
	

Constructor & Destructor Documentation

TiXmlHandle::TiXmlHandle ( TiXmlNode _node) [inline]

Create a handle from any node (at any depth of the tree.) This can be a null pointer.

Referenced by Child(), ChildElement(), FirstChild(), and FirstChildElement().

TiXmlHandle::TiXmlHandle ( const TiXmlHandle ref) [inline]

Copy constructor.

References node.


Member Function Documentation

TiXmlHandle TiXmlHandle::operator= ( const TiXmlHandle ref) [inline]

References node.

TiXmlHandle TiXmlHandle::FirstChild ( ) const

Return a handle to the first child node.

References TiXmlHandle().

TiXmlHandle TiXmlHandle::FirstChild ( const char *  value) const

Return a handle to the first child node with the given name.

References TiXmlHandle().

TiXmlHandle TiXmlHandle::FirstChildElement ( ) const

Return a handle to the first child element.

References TiXmlHandle().

TiXmlHandle TiXmlHandle::FirstChildElement ( const char *  value) const

Return a handle to the first child element with the given name.

References TiXmlHandle().

TiXmlHandle TiXmlHandle::Child ( const char *  value,
int  index 
) const

Return a handle to the "index" child with the given name. The first child is 0, the second 1, etc.

References TiXmlNode::NextSibling(), and TiXmlHandle().

TiXmlHandle TiXmlHandle::Child ( int  index) const

Return a handle to the "index" child. The first child is 0, the second 1, etc.

References TiXmlNode::NextSibling(), and TiXmlHandle().

TiXmlHandle TiXmlHandle::ChildElement ( const char *  value,
int  index 
) const

Return a handle to the "index" child element with the given name. The first child element is 0, the second 1, etc. Note that only TiXmlElements are indexed: other types are not counted.

References TiXmlNode::NextSiblingElement(), and TiXmlHandle().

TiXmlHandle TiXmlHandle::ChildElement ( int  index) const

Return a handle to the "index" child element. The first child element is 0, the second 1, etc. Note that only TiXmlElements are indexed: other types are not counted.

References TiXmlNode::NextSiblingElement(), and TiXmlHandle().

TiXmlNode* TiXmlHandle::ToNode ( ) const [inline]

Return the handle as a TiXmlNode. This may return null.

References node.

Referenced by Node().

TiXmlElement* TiXmlHandle::ToElement ( ) const [inline]

Return the handle as a TiXmlElement. This may return null.

Referenced by Element().

TiXmlText* TiXmlHandle::ToText ( ) const [inline]

Return the handle as a TiXmlText. This may return null.

Referenced by Text().

TiXmlUnknown* TiXmlHandle::ToUnknown ( ) const [inline]

Return the handle as a TiXmlUnknown. This may return null.

Referenced by Unknown().

TiXmlNode* TiXmlHandle::Node ( ) const [inline]
Deprecated:
use ToNode. Return the handle as a TiXmlNode. This may return null.

References ToNode().

TiXmlElement* TiXmlHandle::Element ( ) const [inline]
Deprecated:
use ToElement. Return the handle as a TiXmlElement. This may return null.

References ToElement().

TiXmlText* TiXmlHandle::Text ( ) const [inline]
Deprecated:
use ToText() Return the handle as a TiXmlText. This may return null.

References ToText().

TiXmlUnknown* TiXmlHandle::Unknown ( ) const [inline]
Deprecated:
use ToUnknown() Return the handle as a TiXmlUnknown. This may return null.

References ToUnknown().


Member Data Documentation

Referenced by operator=(), TiXmlHandle(), and ToNode().


The documentation for this class was generated from the following files:

Generated on Fri Dec 23 2011 09:28:55 for MTK++ by Doxygen 1.7.5.1