class ValidatorUtil {
  String? emailValidator(value) {
    if (value == null || value == '') {
      return 'Email is required';
    }
    final String regexEmail =
        "^\\w+([-+.]\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*\$";
    if (value == null || value.isEmpty) return null;
    return new RegExp(regexEmail).hasMatch(value) ? null : 'Email format error';
  }
}