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wp_unique_id() WP 5.0.3

Get unique ID.

This is a PHP implementation of Underscore's uniqueId method. A static variable contains an integer that is incremented with each call. This number is returned with the optional prefix. As such the returned value is not universally unique, but it is unique across the life of the PHP process.

  • Static. Int. $id_counter

No Hooks.

Return

String. Unique ID.

Usage

wp_unique_id( $prefix );
$prefix(string)
Prefix for the returned ID.
Default: ''

Code of wp unique id: wp-includes/functions.php WP 5.2.2

<?php
function wp_unique_id( $prefix = '' ) {
	static $id_counter = 0;
	return $prefix . (string) ++$id_counter;
}