Code: Select all
<script type="text/javascript">
var b = "";
function checkNumber()
{
var a = document.getElementById('amount').value
if(isNaN(a))
{
b = "Value must be a number";
}
}
</script>Code: Select all
<input type="text" name="amount" id="amount" onchange="checkNumber()"/>
<script type="text/javascript">
document.write(b);
</script> Thanks