PHP Tutorial - PHP xml _set _processing _instruction _handler () Function

The xml_set_processing_instruction_handler() function specifies a function to be called when the parser finds a processing instruction in the XML document.

A processing instruction is enclosed in <? and ?> delimiters and contains a a target followed by data.

Syntax

PHP xml_set_processing_instruction_handler() Function has the following syntax.

xml_set_processing_instruction_handler(parser,handler)

Parameter

Parameter	Is Required	Description
parser	Required.	XML parser to use
handler	Required.	A function to be when the parser finds a notation declaration

The Function specified by the "handler" parameter must have three parameters:

Parameter	is Required	Description
parser	Required.	A variable containing the XML parser calling the handler
target	Required.	A variable containing processing instruction target
data	Required.	A variable containing processing instruction data

Return

This function returns TRUE on success, or FALSE on failure.

Example

XML File

<?xml version="1.0" encoding="ISO-8859-1"?>
<?xml-stylesheet href="default.xsl" type="text/xml"?>
<Book>
    <name>PHP</name>
    <name>Java</name>
</Book>

Specify a function to be called when the parser finds a processing instruction in the XML document


<?php //from w  w  w . ja  v a2 s.  c o  m

$parser=xml_parser_create();

function char($parser,$data){
  echo $data;
}

function pi_handler($parser, $target, $data){
  echo "Target: $target";
  echo "Data: $data ";
}

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);
?>