/*
JavaScript Bible, Fourth Edition
by Danny Goodman
John Wiley & Sons CopyRight 2001
*/
<HTML>
<HEAD>
<TITLE>Letting Only Numbers Pass to a Form Field</TITLE>
<SCRIPT LANGUAGE="JavaScript">
function checkIt(evt) {
evt = (evt) ? evt : window.event
var charCode = (evt.which) ? evt.which : evt.keyCode
if (charCode > 31 && (charCode < 48 || charCode > 57)) {
status = "This field accepts numbers only."
return false
}
status = ""
return true
}
</SCRIPT>
</HEAD>
<BODY>
<H1>Letting Only Numbers Pass to a Form Field</H1>
<HR>
<FORM onSubmit="return false">
Enter any positive integer: <INPUT TYPE="text" NAME="numeric"
onKeyPress="return checkIt(event)">
</FORM>
</BODY>
</HTML>