xml_set_processing_instruction_handler
Set up processing instruction (PI) handler
Description
true xml_set_processing_instruction_handler(XMLParser $parser, callable $handler)
A processing instruction has the following format:
Caution
PHP code is delimited by the <?php
processing instruction.
As such it is possible to have PHP code within an XML document.
However, the PI end tag (?>) must not be part of
the data.
If a PI end tag exists as part of the embedded PHP code,
the rest of the PHP code and the "real" PI end tag, will be treated
as character data.
Parameters
-
parser
-
The XML parser.
-
handler
-
If null is passed, the handler is reset to its default state.
Warning
An empty string will also reset the handler,
however this is deprecated as of PHP 8.4.0.
If handler is a callable,
the callable is set as the handler.
If handler is a string,
it can be the name of a method of an object set with
xml_set_object.
Warning
This is deprecated as of PHP 8.4.0.
Warning
As of PHP 8.4.0, the callable is checked to be valid while setting the handler,
not when it is called.
This means that xml_set_object must be called prior to
setting a method string as the callback.
However, as this behaviour is also deprecated as of PHP 8.4.0,
using a proper callable for the method is recommended instead.
The signature of the handler must be:
void handler(XMLParser $parser, string $target, string $data)
-
parser
-
The XML parser calling the handler.
-
target
-
The processing instruction target.
-
data
-
The processing instruction data.
Return Values
Always returns true.