Skip to content
Related Articles

Related Articles

PHP | DOMDocument validate() Function
  • Last Updated : 26 Feb, 2020

The DOMDocument::validate() function is an inbuilt function in PHP which is used to validate the document based on its DTD (Document Type Definition). DTD defines the rules or structure to be followed by the XML file and if a XML document doesn’t follows this format then this function will return false.

Syntax:

bool DOMDocument::validate( void )

Parameters: This function doesn’t accept any parameters.

Return Value: This function returns TRUE if document follows the DTD or FALSE.

Below examples illustrate the DOMDocument::validate() function in PHP:



Example 1:

filter_none

edit
close

play_arrow

link
brightness_4
code

<?php
  
// Create a new DOMDocument
$doc = new DOMDocument;
  
// Load the XML with DTD rule to have
// a root element with first, second,
// and third as its three children
$doc->loadXML("<?xml version=\"1.0\"?>
<!DOCTYPE root [
<!ELEMENT root (first, second, third)>
<!ELEMENT first (#PCDATA)>
<!ELEMENT second (#PCDATA)>
<!ELEMENT third (#PCDATA)>
]>
  
<!-- Create a XML following the DTD -->
<root>
<first>Hello</first>
<second>There</second>
<third>World</third>
</root>");
  
// Check if XML follows the DTD rule
if ($doc->validate()) {
    echo "This document is valid!\n";
}
?>

chevron_right


Output:

This document is valid!

Example 2:

filter_none

edit
close

play_arrow

link
brightness_4
code

<?php
  
// Create a new DOMDocument
$doc = new DOMDocument;
  
// Load the XML
$doc->loadXML("<?xml version=\"1.0\"?>
<!DOCTYPE root [
<!ELEMENT root (one, two, three)>
<!ELEMENT one (#PCDATA)>
<!ELEMENT two (#PCDATA)>
<!ELEMENT three (#PCDATA)>
]>
<!-- Create a XML voilating the DTD -->
  
<root>
<one>Hello</one>
<two>World</two>
</root>");
  
if (!$doc->validate()) {
    echo "This document is not valid!";
}
?>

chevron_right


Output:

This document is not valid!

Reference: https://www.php.net/manual/en/domdocument.validate.php

My Personal Notes arrow_drop_up
Recommended Articles
Page :