Question

I would like to replicate jQuery’s addClass function using plain javascript
So far, I have made this function:

function addClass(el,cl){
el.className+=(el.className?' ':'')+cl
}

It works well, but It uses this syntax:

addClass(element,class)

I want it to use this syntax:

element.addClass(class)

How can I do that?

thanks 🙂

Answer 1

You can make it a prototype to extend the Element class.

Element.prototype.addClass = function(cl) {
    this.className+=(this.className?' ':'')+cl;
}

example

As minitech pointed out though, this won’t work reliably in all browsers (namely IE).