How can I select an element with multiple classes in jQuery?

Question

I want to select all the elements that have the two classes a and b.

So, only the e

Answer 1

Group Selector

body {font-size: 12px; }
body {font-family: arial, helvetica, sans-serif;}
th {font-size: 12px; font-family: arial, helvetica, sans-serif;}
td {font-size: 12px; font-family: arial, helvetica, sans-serif;}

Becomes this:

body, th, td {font-size: 12px; font-family: arial, helvetica, sans-serif;}

So in your case you have tried the group selector whereas its an intersection

$(".a, .b") 

instead use this

$(".a.b")