I have a radio button, and when it is pressed a function is called, which accepts the class of the button as an argument. So something like this:

<input class=myclass type=radio name=name value=x checked=true onClick=myFunction(this.value, this.getAttribute('class'))></input>

Notice that in my onClick, I have this.getAttribute('class') instead of simply this.class. I tried using this.class but I kept getting undefined. Is this.class not an acceptable thing to do? I have used this.id elsewhere in my code which works fine, but for some reason I need to use getAttribute when I want to reference class.

So essentially I am asking what is the difference between this.class and this.getAttribute('class')?