TiXmlHandle Class Reference

Wraps a node pointer. More...

#include <edelib/TiXml.h>

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

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
*   }
* 

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

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