PHP | DOMImplementation hasFeature() Function

The DOMImplementation::hasFeature() function is an inbuilt function in PHP which is used to test if the DOM implementation implements a specific feature or not.

Syntax:

bool DOMImplementation::hasFeature( string $feature, string $version )

Parameters: This function accepts two parameters as mentioned above and described below:

• $feature: It specifies the feature to test.
• $version: It specifies the version number of the feature to test.

Return Value: This function returns TRUE on success or FALSE on failure.

Exceptions: This function throws E_STRICT exception on error.

Below examples illustrate the DOMImplementation::hasFeature() function in PHP:

Example 1:

<?php

// Write the feature name
$featureName1 = "Core";

// Check if it exists
$hasFeature1 =
    DOMImplementation::hasFeature($featureName1, '1.0');
if ($hasFeature1) {
    echo "Has feature $featureName1 module <br>";
}

// Write another feature name
$featureName2 = "XML";

// Check if it exists
$hasFeature2 =
    DOMImplementation::hasFeature($featureName2, '2.0');
if ($hasFeature2) {
    echo "Has feature $featureName2 module <br>";
}
?>

Output:

Has feature Core module
Has feature XML module

Example 2:

<?php
// Write the feature name
$featureName1 = "Events";

// Check if it doesn't exists
$hasFeature1 =
    DOMImplementation::hasFeature($featureName1, '1.0');
if (!$hasFeature1) {
    echo "Doesn't have feature $featureName1 module. <br>";
}

// Write another feature name
$featureName2 = "CSS";

// Check if it doesn't exists
$hasFeature2 =
    DOMImplementation::hasFeature($featureName2, '2.0');
if (!$hasFeature2) {
    echo "Doesn't have feature $featureName2 module. <br>";
}
?>

Output:

Doesn't have feature Events module.
Doesn't have feature CSS module.

Reference: https://www.php.net/manual/en/domimplementation.hasfeature.php