Special Characters In Name

[JynX]

Hello there,

I've recently encountered an issue that I never realized was an issue until now. I'm looking for a fix to remove the ability to use special characters such as lightning bolts, stars, skulls, and any other special characters in people's username. I've searched both here and the rival forums as well as Google itself, so if you could help I'd greatly appreciate it.

Spoiler: Screenshot

 

[JayC]

Put a test on the register page to make sure they only put valid characters?

 

[Joe]

final public function validName($username) 
{
    if(strlen($username) <= 25 && preg_match("/^[a-zA-Z0-9]+$/", $username))
    {         
        return true;     
    }             

    return false;
}