Input URL Validation - General

Hi All

Just a quick question, I have a form that companies write their contact details in I wish to validate some of that information, I already validate the email address with the following
[code]
<?php
$regex = "^[A-Z0-9._%-]+@[A-Z0-9.-]+\.[A-Z]{2,4}\$"
if(!preg_match($regex, $email))
die("Invalid Email!");
else
{
//....
}
?>
[/code]

I was just wondering if it was viable to use Regex to check for the URL they put in as I will not know any information about length etc language etc etc. I have a small function that strips off the "HTTP://" if its there,  I was just wondering if it was a viable option to check the rest??

Yes, there are many [url=http://www.google.com/search?hl=en&lr=&q=url+validation+regex&btnG=Search]out there[/url]. It all depends on how detailed you want to be, what kinds of URLs you want to accept (ftp, e.g.), and how well you understand the specification.

thanks effigy, did somr searching and came up with this
[code]
<?php
function isValidDomain($domainName)
{
return ereg("^(http|https)://(www\.)?.+\.[a-z]{2,7}$", $domainName);
}
?>
[/code]
it will do what I want, i am just checking for typos inthe construct of the url and to make sure they dont just type rubbish in the box

I would use preg and change[tt] (http|https) [/tt]to[tt] (?:https?)[/tt]. Depending on where your data is coming from, you may want to use[tt] \z [/tt]instead of[tt] $[/tt].