Retrieves a modified URL query string. Description You can rebuild the URL and append query variables to the URL query by using this function. There are two ways to use this function; either a single key and value, or an associative array. Using a single key and value: add_query_arg( 'key', 'value', 'http://example.com' ); Using an associative array: add_query_arg( array( 'key1' => 'value1', 'key2