Answers for "add class"

js add class

var element = document.getElementById('element');
element.classList.add('class-1');
element.classList.add('class-2', 'class-3');
element.classList.remove('class-3');

jquery addclass

$("#elem").addClass("classname");

addclass jquery

$( "p" ).addClass( "myClass yourClass" );

add class jquery

$("#my_id").attr("class", "my_new_class_name");

jquery addclass

$( "p" ).removeClass( "myClass noClass" ).addClass( "yourClass" );

addclass javascript

var someElement= document.getElementById("myElement");
    someElement.className += " newclass";//add "newclass" to element (space in front is important)