Javascript: How do I check if the key pressed on a form field is a digit (0 - 9)?

Question

I'm using the onkeyup event on a form field in JavaScript, and I'm wanting to check if the key the key pressed is a numeric digit - ie. 0 - 9, so I can then do something with the input.

<input type="text" onkeyup="" />

Would I need to use Regex for this?

Thanks

Answer 1

See these:

• http://stackoverflow.com/questions/469357/html-text-input-allow-only-numeric-input
• http://stackoverflow.com/questions/724217/allow-digits-only-for-inputs

Answer 2

See this:

http://www.javascriptkit.com/javatutors/javascriptkey2.shtml

<script type="text/javascript">
function displayunicode(e){
var unicode=e.keyCode? e.keyCode : e.charCode
if unicode >= 48 && unicode <= 57 {
    alert('number')
}
else{
}
    alert('nonnumber')
}
</script>
<form>
<input type="text" size="2" maxlength="1" onkeyup="displayunicode(event); this.select()" />
</form>