FluentValidation - 跨多个属性进行验证

Question

有一个表单，用户可以在其中输入活动的开始日期/时间和结束日期/时间。这是目前的验证器：

public class EventModelValidator : AbstractValidator<EventViewModel>
    {
        public EventModelValidator()
        {
            RuleFor(x => x.StartDate)
                .NotEmpty().WithMessage("Date is required!")
                .Must(BeAValidDate).WithMessage("Invalid date");
            RuleFor(x => x.StartTime)
                .NotEmpty().WithMessage("Start time is required!")
                .Must(BeAValidTime).WithMessage("Invalid Start time");
            RuleFor(x => x.EndTime)
                .NotEmpty().WithMessage("End time is required!")
                .Must(BeAValidTime).WithMessage("Invalid End time");
            RuleFor(x => x.Title).NotEmpty().WithMessage("A title is required!");
        }


        private bool BeAValidDate(string value)
        {
            DateTime date;
            return DateTime.TryParse(value, out date);
        }

        private bool BeAValidTime(string value)
        {
            DateTimeOffset offset;
            return DateTimeOffset.TryParse(value, out offset);
        }

    }

现在我还想添加 EndDateTime > StartDateTime（组合日期+时间属性）的验证，但不知道如何去做。

编辑： 为了澄清，我需要以某种方式结合 EndDate + EndTime/StartDate + StartTime 即 DateTime.Parse(src.StartDate + " " + src.StartTime) 然后验证 EndDateTime 与 StartDateTime - 我该怎么做？

Answer 1

您可以尝试使用GreaterThan 规则：

RuleFor(x => x.EndDate)
    .GreaterThan(x => x.StartDate)
    .WithMessage("end date must be after start date");

Answer 2

在我重新阅读documentation 后终于让它工作了：“请注意，Must 还有一个额外的重载，它也接受正在验证的父对象的实例。”

public class EventModelValidator : AbstractValidator<EventViewModel>
    {
        public EventModelValidator()
        {
            RuleFor(x => x.StartDate)
                .NotEmpty().WithMessage("Date is required!")
                .Must(BeAValidDate).WithMessage("Invalid date");
            RuleFor(x => x.StartTime)
                .NotEmpty().WithMessage("Start time is required!")
                .Must(BeAValidTime).WithMessage("Invalid Start time");
            RuleFor(x => x.EndTime)
                .NotEmpty().WithMessage("End time is required!")
                .Must(BeAValidTime).WithMessage("Invalid End time")
                // new
                .Must(BeGreaterThan).WithMessage("End time needs to be greater than start time");
            RuleFor(x => x.Title).NotEmpty().WithMessage("A title is required!");
        }


        private bool BeAValidDate(string value)
        {
            DateTime date;
            return DateTime.TryParse(value, out date);
        }

        private bool BeAValidTime(string value)
        {
            DateTimeOffset offset;
            return DateTimeOffset.TryParse(value, out offset);
        }
        // new
        private bool BeGreaterThan(EventViewModel instance, string endTime)
        {
            DateTime start = DateTime.Parse(instance.StartDate + " " + instance.StartTime);
            DateTime end = DateTime.Parse(instance.EndDate + " " + instance.EndTime);
            return (DateTime.Compare(start, end) <= 0);
        }
    }

可能有一种更简洁/更优雅的方式来做到这一点，但目前，它可以正常工作。