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function is not described

add_cssclass() WP 1.0

No Hooks.

Return

String.

Usage

add_cssclass( $add, $class );
$add(string) (required)
-
$class(string) (required)
-

Code of add_cssclass() WP 5.8.2

function add_cssclass( $add, $class ) {
	$class = empty( $class ) ? $add : $class .= ' ' . $add;
	return $class;
}