input restriction

[jaymc]

I want to make it so on an input field on my form members can only type numbers and letters and no other characters

I was pretty sure their was a special html element that could achieve this but ive googled and havnt found anything

If not, does anyone have a javascript that will do this

Thanks!

[nogray]

You can use regular expressions for that, here is a small sample
[code]
<script type="text/javascript">

function cF(){
if (document.getElementById('input_field').value.search(/^[a-zA-Z0-9]+$/) == -1){
alert("invalid value");
return false;
}
}

</script>

<form method="post" action="#" onSubmit="return cF()">
<input type="text" name="input_field" id="input_field" />
<input type="submit" value="Click" />
</form>
[/code]

[jaymc]

I was thinking of something that simply wouldnt allow them to type it in the first place rather than have alerts..

Is their for sure no HTML alternitive?

[nogray]

No, there is no HTML alternitive. If you don't want them to type it in the first place, you gotta add an onkeypress event and check the value each time the key is pressed.

[jaymc]

Cheers guys