pattern static method

NiceValidationRule pattern(
  1. RegExp regex, {
  2. String? message,
})

String must match pattern.

Implementation

static NiceValidationRule pattern(RegExp regex, {String? message}) =>
    (value) {
      if (value is String && value.isNotEmpty && !regex.hasMatch(value)) {
        return message ?? 'Invalid format';
      }
      return null;
    };