TiXmlHandle Class Reference

Wraps a node pointer. More...

#include <edelib/TiXml.h>

List of all members.

Public Member Functions
	TiXmlHandle (TiXmlNode *_node)
	TiXmlHandle (const TiXmlHandle &ref)
TiXmlHandle	operator= (const TiXmlHandle &ref)
TiXmlHandle	FirstChild () const
TiXmlHandle	FirstChild (const char *value) const
TiXmlHandle	FirstChildElement () const
TiXmlHandle	FirstChildElement (const char *value) const
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
TiXmlNode *	ToNode () const
TiXmlElement *	ToElement () const
TiXmlText *	ToText () const
TiXmlUnknown *	ToUnknown () const
TiXmlNode *	Node () const
TiXmlElement *	Element () const
TiXmlText *	Text () const
TiXmlUnknown *	Unknown () const

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Detailed Description

Wraps a node pointer.

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
 *   }
 * 

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Constructor & Destructor Documentation

TiXmlHandle ( TiXmlNode *  _node )

inline

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

TiXmlHandle ( const TiXmlHandle &  ref )

inline

Copy constructor

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Member Function Documentation

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.

TiXmlHandle Child

(

int

index

)

const

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

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.

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.

TiXmlElement* Element ( ) const

inline

Deprecated:

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

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.

TiXmlNode* Node ( ) const

inline

Deprecated:

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

TiXmlHandle operator= ( const TiXmlHandle &  ref )

inline

Assignement from TiXmlHandle

TiXmlText* Text ( ) const

inline

Deprecated:

use ToText() Return the handle as a TiXmlText. This may return null.

TiXmlElement* ToElement ( ) const

inline

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

TiXmlNode* ToNode ( ) const

inline

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

TiXmlText* ToText ( ) const

inline

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

TiXmlUnknown* ToUnknown ( ) const

inline

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

TiXmlUnknown* Unknown ( ) const

inline

Deprecated:

use ToUnknown() Return the handle as a TiXmlUnknown. This may return null.

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

• edelib/TiXml.h