PHP xml_set_processing_instruction_handler() function
Definition and Usage
The xml_set_processing_instruction_handler() function defines the function to be called when the parser finds a processing instruction in the XML document.
The processing instruction is enclosed in <? and ?> delimiters.
If the handler is successfully established, the function will return true; otherwise, it will return false.
Example: In this example, the processing instruction associates a stylesheet with the XML document:
<?xml version="1.0" encoding="ISO-8859-1"?> <?xml-stylesheet href="default.xsl" type="text/xml"?> <note> <to>Tove</to> <from>Jani</from> <heading>Reminder</heading> <body>Don't forget me this weekend!</body> </note>
Syntax
xml_set_processing_instruction_handler(parser,handler)
| Parameter | Description |
|---|---|
| parser | Mandatory. Defines the XML parser to be used. |
| handler | Mandatory. Defines a function. |
By handler The function defined by the parameter must have three parameters:
| Parameter | Description |
|---|---|
| parser | Mandatory. Defines a variable that contains the XML parser used by the handler. |
| target | Required. Specifies the variable that contains the processing instruction target. |
| data | Required. Specifies the variable that contains the processing instruction data. |
Description
handler The parameter can also be an array containing object references and method names.
Example
<?php
$parser=xml_parser_create();
function char($parser,$data)
{
echo $data;
}
function pi_handler($parser, $target, $data)
{
echo "Target: $target<br />";
echo "Data: $data<br />";
}
xml_set_character_data_handler($parser,"char");
xml_set_processing_instruction_handler($parser, "pi_handler");
$fp=fopen("test.xml","r");
while ($data=fread($fp,4096))
{
xml_parse($parser,$data,feof($fp)) or
die (sprintf("XML Error: %s at line %d",
xml_error_string(xml_get_error_code($parser)),
xml_get_current_line_number($parser)));
}
xml_parser_free($parser);
?>
