Question

Let say

 <div id = "test_id" class = "test_class"> </div>

JS

  alert( $("#test_id").hasClass('test_class') );  // result is true

I just write another way to get the same expected result but didn’t work, Why?

 var test = ' " ' + "test_id" + ' " ' ;

      alert( $(test).hasClass('test_class')  );    // not working, why ?????

Answer 1

The variable ‘test’ needs to be in the format of an ID selector – i.e. #test

So it should be:

var test = '#test_id';
alert( $(test).hasClass('test_class') );