使用FluentValidation来进行数据有效性验证

之前我介绍过了使用系统自带的Data Annotations来进行数据有效性验证，今天在CodePlex上逛的时候，发现了一个非常简洁好用的库：FluentValidation

由于非常简洁，就直接拿官网的例子演示了： 

    using FluentValidation;

    public class CustomerValidator : AbstractValidator<Customer>
    {
        public CustomerValidator()
        {
            RuleFor(customer => customer.Surname).NotEmpty();
            RuleFor(customer => customer.Forename).NotEmpty().WithMessage("Please specify a first name");
            RuleFor(customer => customer.Discount).NotEqual(0).When(customer => customer.HasDiscount);
            RuleFor(customer => customer.Address).Length(20, 250);
            RuleFor(customer => customer.Postcode).Must(BeAValidPostcode).WithMessage("Please specify a valid postcode");
        }

        private bool BeAValidPostcode(string postcode)
        {
            // custom postcode validating logic goes here
        }
    }

    Customer customer = new Customer();
    CustomerValidator validator = new CustomerValidator();
    ValidationResult results = validator.Validate(customer);

    bool validationSucceeded = results.IsValid;
    IList<ValidationFailure> failures = results.Errors;

它还可以非常方便的与Asp.Net集成，用起来非常方便。官网的帮助文档也非常详尽，有数据有效性检验的朋友赶紧用起来把。