required static method

NiceValidationRule required({
  1. String? message,
})

Value must not be null or empty.

Implementation

static NiceValidationRule required({String? message}) => (value) {
      if (value == null) return message ?? 'This field is required';
      if (value is String && value.trim().isEmpty) {
        return message ?? 'This field is required';
      }
      return null;
    };