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TiXmlHandle Class Reference

** 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. More...

Public Member Functions

 __init__ (const TiXmlHandle ref)
 Copy constructor. More...
 
 __init__ (TiXmlNode _node)
 Create a handle from any node (at any depth of the tree.) This can be a null pointer. More...
 
TiXmlHandle Child (str value, int index)
 ** Return a handle to the "index" child with the given name. The first child is 0, the second 1, etc. */ More...
 
TiXmlHandle Child (int index)
 ** Return a handle to the "index" child. The first child is 0, the second 1, etc. */ More...
 
TiXmlHandle Child (str _value, int index)
 
TiXmlHandle ChildElement (str value, int index)
 ** 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. */ More...
 
TiXmlHandle ChildElement (int index)
 ** 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. */ More...
 
TiXmlHandle ChildElement (str _value, int index)
 
TiXmlElement Element ()
 ** More...
 
TiXmlHandle FirstChild ()
 Return a handle to the first child node. More...
 
TiXmlHandle FirstChild (str value)
 Return a handle to the first child node with the given name. More...
 
TiXmlHandle FirstChild (str _value)
 
TiXmlHandle FirstChildElement ()
 Return a handle to the first child element. More...
 
TiXmlHandle FirstChildElement (str value)
 Return a handle to the first child element with the given name. More...
 
TiXmlHandle FirstChildElement (str _value)
 
TiXmlNode Node ()
 ** More...
 
TiXmlHandle operator= (const TiXmlHandle ref)
 
TiXmlText Text ()
 ** More...
 
TiXmlElement ToElement ()
 ** Return the handle as a TiXmlElement. This may return null. */ More...
 
TiXmlNode ToNode ()
 ** Return the handle as a TiXmlNode. This may return null. */ More...
 
TiXmlText ToText ()
 ** Return the handle as a TiXmlText. This may return null. */ More...
 
TiXmlUnknown ToUnknown ()
 ** Return the handle as a TiXmlUnknown. This may return null. */ More...
 
TiXmlUnknown Unknown ()
 ** More...
 

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
}

*/

Member Function Documentation

◆ __init__() [1/2]

__init__ ( const TiXmlHandle  ref)

Copy constructor.

◆ __init__() [2/2]

__init__ ( TiXmlNode  _node)

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

◆ Child() [1/3]

TiXmlHandle Child ( str  value,
int  index 
)

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

◆ Child() [2/3]

TiXmlHandle Child ( int  index)

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

◆ Child() [3/3]

TiXmlHandle Child ( str  _value,
int  index 
)

◆ ChildElement() [1/3]

TiXmlHandle ChildElement ( str  value,
int  index 
)

** 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. */

◆ ChildElement() [2/3]

TiXmlHandle ChildElement ( int  index)

** 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. */

◆ ChildElement() [3/3]

TiXmlHandle ChildElement ( str  _value,
int  index 
)

◆ Element()

TiXmlElement Element ( )

**

◆ FirstChild() [1/3]

TiXmlHandle FirstChild ( )

Return a handle to the first child node.

◆ FirstChild() [2/3]

TiXmlHandle FirstChild ( str  value)

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

◆ FirstChild() [3/3]

TiXmlHandle FirstChild ( str  _value)

◆ FirstChildElement() [1/3]

TiXmlHandle FirstChildElement ( )

Return a handle to the first child element.

◆ FirstChildElement() [2/3]

TiXmlHandle FirstChildElement ( str  value)

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

◆ FirstChildElement() [3/3]

TiXmlHandle FirstChildElement ( str  _value)

◆ Node()

TiXmlNode Node ( )

**

◆ operator=()

TiXmlHandle operator= ( const TiXmlHandle  ref)

◆ Text()

TiXmlText Text ( )

**

◆ ToElement()

TiXmlElement ToElement ( )

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

◆ ToNode()

TiXmlNode ToNode ( )

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

◆ ToText()

TiXmlText ToText ( )

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

◆ ToUnknown()

TiXmlUnknown ToUnknown ( )

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

◆ Unknown()

TiXmlUnknown Unknown ( )

**