email validation with a twist!

I need to strictly block certain email addresses

[benji]

I use J/Script validation on a form.
All seems to work well for me - thanks to Webmasterworld.com!

I keep getting emails from a person using very similar email address to my own (obviously someone I know).

The question is, how can I give them a special Javascript message, if using certain email addresses. Let's assume the email address is:

[e-mail]

The RegExp I already have in place is:

var emailRegExp = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;

I know haw to set the message etc, but can't quite seem to get the speacial email to throw the message up..

I thought replacing the a-zA-Z0-9 with myemail would work, but it doesn't.

All help much appreciated.

[benji]

PS - just a thought....
Is there any way of catching someone's IP address through a contact form?

[whoisgregg]

Hello benji,

Not directly, but you can use the server side language of your choice to pass that information to your javascript. For PHP something like this would work:

<script type="text/javascript">
var user_ip = '<?php echo $_SERVER['REMOTE_ADDR']; ?>';
alert(user_ip); // testing only, use this variable in your existing function
</script>

To block certain email addresses, you'd want to do a separate check from the one to validate the format of the email address. If you post a snippet of your code, we should be able to recommend a place to do so.