sanitize_key( string $key ): string

2187function sanitize_key( $key ) {2188	$sanitized_key = '';2189 2190	if ( is_scalar( $key ) ) {2191		$sanitized_key = strtolower( $key );2192		$sanitized_key = preg_replace( '/[^a-z0-9_\-]/', '', $sanitized_key );2193	}2194 2195	/**2196	 * Filters a sanitized key string.2197	 *2198	 * @since 3.0.02199	 *2200	 * @param string $sanitized_key Sanitized key.2201	 * @param string $key           The key prior to sanitization.2202	 */2203	return apply_filters( 'sanitize_key', $sanitized_key, $key );2204}