sanitize_hex_color

sanitize_hex_color.php

/**
 * Duplicate the sanitize_hex_color function, which is generally
 * only available to the theme customizer.
 */
if ( !function_exists( 'sanitize_hex_color' ) ) {
	function sanitize_hex_color( $color ) {
		if ( '' === $color )
			return '';

		// 3 or 6 hex digits, or the empty string.
		if ( preg_match('|^#([A-Fa-f0-9]{3}){1,2}$|', $color ) )
			return $color;

		return null;
	}
}