[SOLVED] ereg()

[Northern Flame]

I've never used ereg() before,

but am now trying it out.

I want to only allow letters, numbers, and

underscores in my usernames but

the following script doesn't work:

 

<?php
$username = $_POST['username'];
$ereg = ereg("([a-zA-Z0-9_])", $username);
if ($ereg) {
echo $username;
} else {
    echo "Invalid format: $username";
}
?>

 

if I am to input ';;;;;'

it returns "Invalid format: ;;;;;"

but if I enter 'test;'

it returns 'test;' which means

it accepted it, how can I

fix this?

 

Thanks for reading!

[Northern Flame]

never mind i found a fix:

 

<?php
$pattern = '([[:digit:]]|[~`!@#$%^&*(). =+{}|\:;"/?,]|[|]|-)+';
$name = stripslashes($_POST['username']);
if (ereg($pattern, $_POST['username'])) {
echo "error";
} else{
echo "ok";
}
?>