电子邮箱正则验证

<?php
$user_email = "lin3615@xx.xx";

function is_email($user_email)
{
    $chars = "/^([a-z0-9+_]|\\-|\\.)+@(([a-z0-9_]|\\-)+\\.)+[a-z]{2,6}\$/i";
   if (strpos($user_email, '@') !== false && strpos($user_email, '.') !== false)
  {
     if (preg_match($chars, $user_email))
    {
         return true;
   }
    else
   {
      return false;
    }
  }
  else
  {
     return false;
   }
}
?>