// 验证邮件地址
function chkemail($email)
{
    $pattern = '/^([0-9A-Za-z\\-_\\.]+)@([0-9a-z]+\\.[a-z]{2,3}(\\.[a-z]{2})?)$/i';
    if (preg_match($pattern, $email)) {
        return true;
    } else {
        return false;
    }
}