Answers for "if class name exists jquery"

if a class exists jquery

if ($(".mydivclass").length){
    // Do something if class exists
} else {
    // Do something if class does not exist
}

detect if an element has a class jQurey

$("#EL_ID").hasClass("CLASS_NAME");

jquery check if has class

if ($("#about").hasClass("opened")) {
  $("#about").animate({right: "-700px"}, 2000);
}