Limit Textfield Input to digits only

Question

I've searched Google, but all the solutions I could find were really complicated and long. What I need is to limit the input of a textfield in a survey I'm making to digits only. What is the quickest and cleanest way to do this?

(I'm using HTML 4.01 strict and ECMAScript)

Thanks in advance.

Answer 1

The quickest:

<input type="text" onkeyup="this.value = this.value.replace(/\D/g, '')">

That won't stop people from pasting things in with their mouse, so an onchange and onclick are probably desirable, too.

The cleanest (or at least a clean way to do it):

function forceNumeric() {
    this.value = this.value.replace(/\D/g, '');
}

If you're using a JS framework, give all your numeral-only inputs a class that indicates the fact (class="numeric" or something like that), and add forceNumeric as a callback for keyup, change, and click to any input element with that class:

$('.numeric').keyup(forceNumeric).change(forceNumeric).click(forceNumeric);

If you're using straight JS (I'd recommend not using straight JS), either use element.addEventListener, or onkeyup, onchange, and onclick.