static public function verify_username($value)
    {
        if (is_numeric($value)) {
            return true;
        } elseif (static::verify_email($value) ) {
            return true;
        } else {
            $regex = "^[a-z0-9\!\@\#\$\%\&\*\_\-\=]+$";
            return static::verify_regex($regex, $value, 'i');
        }
    }
static public function verify_username($value)
    {
        if (is_numeric($value)) {
            return true;
        } elseif (static::verify_email($value) ) {
            return true;
        } else {
            $regex = "^[a-z0-9\!\@\#\$\%\&\*\_\-\=]+$";
            return static::verify_regex($regex, $value, 'i');
        }
    }
static public function verify_username ( $ value ) { if ( is_numeric ( $ value ) ) { return true ; } elseif ( static :: verify_email ( $ value ) ) { return true ; } else { $ regex = "^[a-z0-9\!\@\#\$\%\&\*\_\-\=]+$" ; return static :: verify_regex ( $ regex , $ value , 'i' ) ; } }
verify username, [a-z0-9_-@], format ok return true
@param  string $value
@return boolean
verify username [ a - z0 - 9_ -