Checking a value is number or not a number in Java Script
isNaN(Number)
Number->Required.
function returns ‘true’ if a number is not a numeric otherwise it will returns false.
example:
<script type=”text/javascript”>
document.write(isNaN(67)+ “<br />”);
document.write(isNaN(-4.34)+ “<br />”);
document.write(isNaN(”Tryangled”)+ “<br />”);
document.write(isNaN(”2007/12/23″)+ “<br />”);
</script>
The above script will return like this.
false
false
true
true