e-mail vertification

[asmith]

i want to put some limits for e-mail vertification (e-mail that a user type in registration form)

but don't know exactlly what symbols i should limit  ,

 

shold i just :

 

(!preg_match("/@/",$_POST['email_address'])

 

is this enough ? or are there any other symbols i should limit beside of checking for @ sign ?

(or e-mail addresses can contain any symbol?)

[~n[EO]n~]

See this

<?php if(!ereg("[0-9a-z]([-_.]?[0-9a-z])*@[0-9a-z]([-.]?[0-9a-z])*\\.[a-z]", $_POST['email_address'])) 
echo "Email not valid"; ?>

[asmith]

<?php if(!ereg("[0-9a-z]([-_.]?[0-9a-z])*@[0-9a-z]([-.]?[0-9a-z])*\\.[a-z]", $_POST['email_address'])) 
echo "Email not valid"; ?>

 

this code accept upper case letters?

what does "?" means ? both side characters can combine ?

[~n[EO]n~]

If you want all the explanations and some examples go here

http://www.phpfreaks.com/forums/index.php/topic,96280.0.html

And, I also found a good way to validate e-mail. That is the board where this question belongs  .