Panda3D
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A TiXmlHandle is a class that wraps a node pointer with null checks; this is an incredibly useful thing. More...
#include <pandadoc.hpp>
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 (int index) |
Return a handle to the "index" child. More... | |
TiXmlHandle | Child (str _value, int index) |
TiXmlHandle | Child (str value, int index) |
Return a handle to the "index" child with the given name. More... | |
TiXmlHandle | ChildElement (int index) |
Return a handle to the "index" child element. More... | |
TiXmlHandle | ChildElement (str _value, int index) |
TiXmlHandle | ChildElement (str value, int index) |
Return a handle to the "index" child element with the given name. More... | |
TiXmlElement | Element () |
TiXmlHandle | FirstChild () |
Return a handle to the first child node. More... | |
TiXmlHandle | FirstChild (str _value) |
TiXmlHandle | FirstChild (str value) |
Return a handle to the first child node with the given name. More... | |
TiXmlHandle | FirstChildElement () |
Return a handle to the first child element. More... | |
TiXmlHandle | FirstChildElement (str _value) |
TiXmlHandle | FirstChildElement (str value) |
Return a handle to the first child element with the given name. More... | |
TiXmlNode | Node () |
TiXmlHandle | operator= (const TiXmlHandle ref) |
TiXmlText | Text () |
TiXmlElement | ToElement () |
Return the handle as a TiXmlElement. More... | |
TiXmlNode | ToNode () |
Return the handle as a TiXmlNode. More... | |
TiXmlText | ToText () |
Return the handle as a TiXmlText. More... | |
TiXmlUnknown | ToUnknown () |
Return the handle as a TiXmlUnknown. More... | |
TiXmlUnknown | Unknown () |
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 }
__init__ | ( | const TiXmlHandle | ref | ) |
Copy constructor.
__init__ | ( | TiXmlNode | _node | ) |
Create a handle from any node (at any depth of the tree.) This can be a null pointer.
TiXmlHandle Child | ( | int | index | ) |
Return a handle to the "index" child.
The first child is 0, the second 1, etc.
TiXmlHandle Child | ( | str | _value, |
int | index | ||
) |
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.
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.
TiXmlHandle ChildElement | ( | 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.
TiXmlElement Element | ( | ) |
TiXmlHandle FirstChild | ( | ) |
Return a handle to the first child node.
TiXmlHandle FirstChild | ( | str | _value | ) |
TiXmlHandle FirstChild | ( | str | value | ) |
Return a handle to the first child node with the given name.
TiXmlHandle FirstChildElement | ( | ) |
Return a handle to the first child element.
TiXmlHandle FirstChildElement | ( | str | _value | ) |
TiXmlHandle FirstChildElement | ( | str | value | ) |
Return a handle to the first child element with the given name.
TiXmlNode Node | ( | ) |
TiXmlHandle operator= | ( | const TiXmlHandle | ref | ) |
TiXmlText Text | ( | ) |
TiXmlElement ToElement | ( | ) |
Return the handle as a TiXmlElement.
This may return null.
TiXmlUnknown ToUnknown | ( | ) |
Return the handle as a TiXmlUnknown.
This may return null.
TiXmlUnknown Unknown | ( | ) |