PHP Script: Require .edu email extension in registration

I am creating a registration page for a college web application. I'm wondering if anyone knows a simple script that I could include in my authentication script to make sure the user registered with a .edu email address?

Thanks in advance

 

Here's two examples

//$email = "some.body@somedomain.edu";
$email = "some.body@somedomain.com";

if (stripos($email,".edu") !== false)
    {
     // echo "Valid e-mail address, processing...";
    } else {
      echo "Please supply a valid .edu email address";
       exit;
    }

PHP:

//$email = "some.body@somedomain.edu";
$email = "some.body@somedomain.com";

if (!preg_match("/^([a-zA-Z0-9])+([\.a-zA-Z0-9_-])*@([a-zA-Z0-9_-])+(\.[a-zA-Z0-9_-]+)*\.edu/", $email)) {
die("Please supply a valid .edu email address");
}else{
// echo "Valid e-mail address, processing...";
}

PHP:

 

Sorry, but these two examples could be bypassed with strings like "user@foo.edu.evildomain.com".

Try something like:

preg_match('%\.edu$%si', $addr)

instead (untested).