add class via jquery but only when not exists

Question

I would like to add a class (class=\"bbox\") to a ul-list but only if no class exists. This is what i have so far. How do I check with jquery if a class exists in the ul-tag

Answer 1

If you want to check if a specific class exists then:

 if(!$("ul").hasClass("class-name")){
    $("ul").addClass("bbox");
 }

If you want to check if any class exists:

if ($('ul').attr('class') == '') {
    $("ul").addClass("bbox");
}