[zz]javascript: Form onsubmit Event
http://ww.w3schools.com/jsref/event_form_onsubmit.asp
<html>
<head>
<script type="text/javascript">
function greeting()
{
alert("Welcome " + document.forms["frm1"]["fname"].value + "!")
}
</script>
</head>
<body>
What is your name?<br />
<form name="frm1" action="submit.htm" onsubmit="greeting()">
<input type="text" name="fname" />
<input type="submit" value="Submit" />
</form>
</body>
</html>
