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Sonia
07-28-2003, 05:04 AM
how do I validate an email textbox to check if the user has not entered 2 @ signs.
Gollum
07-28-2003, 05:23 AM
you could use the String.match() method...

if ( addr.match(/[@]/g).length != 1 ) alert("wrong number of '@' signs");
Charles
07-28-2003, 05:57 AM
This one checks your field against all of the email address naming rules:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta name="Content-Script-Type" content="text/javascript">
<title>Example</title>
<form action="">
<script type="text/javascript">
<!--

String.prototype.isEmailAddress = function () {return this.match(/^[^\x00-\x20()<>@,;:\\".[\]\x7f-\xff]+(?:\.[^\x00-\x20()<>@,;:\\".[\]\x7f-\xff]+)*\@[^\x00-\x20()<>@,;:\\".[\]\x7f-\xff]+(?:\.[^\x00-\x20()<>@,;:\\".[\]\x7f-\xff]+)+$/)}

// -->
</script>
<div>
<input type="text" onchange="if (!this.value.isEmailAddress()) {alert ('That would not appear to be a valid email address.'); this.value=''; this.focus()}">
<input type="submit">
</div>
</form>
Sonia
07-28-2003, 06:00 AM
Can anyone debug that for me!

<html>
<head>
<script>
function val()
{

if (document.frm.addr.match(/[@]/g).length != 1 )
{
window.alert("wrong number of '@' signs");
}
}
</script>
</head>
<body>
<form name = "frm">
Email<input type = "text" name = addr>
<input type = button value = test onClick= "val()">
</form>
</body>
</html>
Gollum
07-28-2003, 06:07 AM
The error is because you are calling document.frm.addr.match() and document.frm.addr.match is an input element, you need a string, so try...

document.frm.addr.value.match(...)

I also realised that if there are no '@' signs, then the function match() returns null, not an array with length zero, so you need to say

var a = document.frm.addr.value.match(/[@]/g);
if ( !a || (a.length != 1) ) alert('...');
Charles
07-28-2003, 06:09 AM
Or just use the one that I posted above.
Sonia
07-28-2003, 06:21 AM
Cool! Working now but wat does the 'g' stands for in the code?

<html>
<head>
<script>
function val()
{

var a = document.frm.addr.value.match(/[@]/g);
if ( !a || (a.length != 1) )
alert('only 1 @ sign');

}
</script>
</head>
<body>
<form name = "frm">
Email<input type = "text" name = addr>
<input type = button value = test onClick= "val()">
</form>
</body>
</html>
Charles
07-28-2003, 06:51 AM
The "g" is a flag and it indicates that the pattern should be matched globally. See http://devedge.netscape.com/library/manuals/2000/javascript/1.3/guide/regexp.html.