<script type="text/javascript">

function handleerror(keyPressEvent)
{
var enteredKey;
if (navigator.appName == "Microsoft Internet Explorer")
enteredKey = keyPressEvent.keyCode;
var enteredChar = String.fromCharCode(enteredKey);
var allowCharacter = true;
try
{
if (isNan(enteredChar))
}
{
throw "This is a non numeric value";
allowCharacter = false;
}
}
catch( error)
{
window.alert(error);
return allowCharacter;
}
finally
{
return allowCharacter;
}
</script>