wp_unique_id_from_values() │ WP 6.8.0

Creates a short identifier from an array's structure and values.

Converts the array to JSON, calculates an MD5 hash, and uses its first 8 characters. Identical arrays create identical identifiers. The order of elements and keys affects the result.

The identifier does not guarantee absolute uniqueness because the hash is shortened to 8 characters. Do not use it as a secret token or where collisions are unacceptable.

Use wp_unique_id() when every call must create a new identifier regardless of the data passed.

No Hooks.

Returns

string.

  • string - an 8-character hash with the specified prefix.

Usage

wp_unique_id_from_values( $data, $prefix ): string;
$data(array) (required)

Data from which to create the identifier.

The array must not be empty. When an empty array is passed, WordPress triggers a _doing_it_wrong() notice but continues execution and creates an identifier.

$prefix(string)
A prefix added before the hash. The prefix is not part of the hash calculation.
Default: ''

Examples

#1 Create a CSS class from settings

An identical set of settings always creates the same class name.

$layout = [
	'layout'  => 'grid',
	'columns' => 3,
	'gap'     => '24px',
];

$class_name = wp_unique_id_from_values( $layout, 'layout-' );

printf(
	'<div class="%s">Content</div>',
	esc_attr( $class_name )
);

Changelog

Since 6.8.0 Introduced.

wp_unique_id_from_values() code WP 7.1.1

wp-includes/functions.php 
function wp_unique_id_from_values( array $data, string $prefix = '' ): string {
	if ( empty( $data ) ) {
		_doing_it_wrong(
			__FUNCTION__,
			sprintf(
				/* translators: %s: The parameter name. */
				__( 'The %s parameter must not be empty.' ),
				'$data'
			),
			'6.8.0'
		);
	}

	$serialized = wp_json_encode( $data );
	$hash       = substr( md5( $serialized ), 0, 8 );

	return $prefix . $hash;
}

JSON (json related)

Supporting (helper utility auxiliary)

Helper Functions