note 54956 rejected from function.strpos by sean
| From: | sean@php.net | Date: | Wed, 20 Jul 2005 19:00:58 +0000 |
| Subject: | note 54956 rejected from function.strpos by sean | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-92225@lists.php.net to get a copy of this message | ||
Note Submitter: krydprz at iit dot edu
----
Here's my stab at email address verification/correctness function. The parameter the function
takes is an email address such as foo@bar.net. I hope somebody finds it useful.
<?php
function check_email_integrity($email_str)
{
$ret_val = FALSE;
while(1)
{
// an email of form a@b.c has a minimum of 5 characters
if (strlen($email_str) < 5)
break;
// this will eliminate all combinations when 2 or more 'at' symbols are together
$which = strpos($email_str, "@@");
if ($which !== FALSE)
break;
// this will eliminate all combinations when 2 or more dots are together
$which = strpos($email_str, "..");
if ($which !== FALSE)
break;
$which = strpos($email_str, ".@");
if ($which !== FALSE)
break;
$which = strpos($email_str, "@.");
if ($which !== FALSE)
break;
$which = strpos($email_str, "@");
if ($which === FALSE || $which == 0 || $which > strlen($email_str) - 4)
break;
$which = strpos($email_str, ".");
if ($which === FALSE || $which == 0 || $which == strlen($email_str) - 1)
break;
$which = strpos(strrev($email_str), "@");
if ($which === FALSE || $which == 0 || $which > strlen($email_str) - 4)
break;
$which = strpos(strrev($email_str), ".");
if ($which === FALSE || $which == 0 || $which == strlen($email_str) - 1)
break;
$prefix_suffix = explode("@", $email_str);
// check if perhaps more than 2 array elements result which would mean
// that more than one '@' exists in the string
if (count($prefix_suffix) != 2)
break;
if (strlen($prefix_suffix[1]) < 3)
break;
$which = strpos($prefix_suffix[1], ".");
if ($which === FALSE || $which == 0 || $which == strlen($email_str) - 1)
break;
// we have a valid email address finally
$ret_val = TRUE;
break;
}
return $ret_val;
}
?>
If someone finds it useful, here's the same thing in Javascript:
function verify_email(email_to_verify)
{
var return_val = false;
var email_str = email_to_verify;
while(1)
{
if (email_str.length < 5)
break;
var which = email_str.indexOf("@@");
if (which != -1)
break;
which = email_str.indexOf("..");
if (which != -1)
break;
var which = email_str.indexOf(".@");
if (which != -1)
break;
which = email_str.indexOf("@.");
if (which != -1)
break;
which = email_str.indexOf("@");
if (which == -1 || which == 0 || which > email_str.length - 4)
break;
which = email_str.indexOf(".");
if (which == -1 || which == 0 || which == email_str.length - 1)
break;
which = email_str.lastIndexOf("@");
if (which == -1 || which == 0 || which > email_str.length - 4)
break;
which = email_str.lastIndexOf(".");
if (which == -1 || which == 0 || which == email_str.length - 1)
break;
var prefix_suffix = email_str.split("@");
// check if perhaps more than 2 array elements result which would mean
// that more than one '@' exists in the string
if (prefix_suffix.length != 2)
break;
if (prefix_suffix[1].length < 3)
break;
which = prefix_suffix[1].indexOf(".");
if (which == -1 || which == 0 || which == email_str.length - 1)
break;
// we have a valid email address finally
return_val = true;
break;
}
if (return_val == false)
alert ("You must provide a valid email address.");
return return_val;
}
Kind Regards,
Przemek