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How can I cancel a key press?
Can I filter out particular keys in text field/text area input?

Feb 17th, 2000 18:28
Martin Honnen, 


NN4 and IE5 allow to cancel key presses by returning false in the 
onkeydown event handler; you can use that to filter out numerical keys 
for example:

<SCRIPT>
function validateNonNumber (evt) {
  var keyCode = evt.which ? evt.which : evt.keyCode;
  return keyCode < '0'.charCodeAt() || keyCode > '9'.charCodeAt(); 
}
</SCRIPT>
</HEAD>
<BODY>
<FORM NAME="aForm">
<INPUT TYPE="text" NAME="field"
       ONKEYDOWN="return false"
>
<BR>
<INPUT TYPE="text" NAME="aField"
       ONKEYDOWN="return validateNonNumber(event)"
>
</FORM>