c# - FluentValidation:检查两个字段之一是否为空

Question

我有这个模型

public class Person
{
    public int Id { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }  
}

我想创建一个验证，其中 FirstName 或 LastName 必须由用户填写。 我安装了 FluentValidation 并创建了一个customvalidator 类

public class PersonValidator:AbstractValidator<Person>
{
    public PersonValidator()
    {
        RuleFor((person=>person.FirstName)//don't know how to check if one is empty
    }
}

要只检查一个字段，我可以执行 RuleFor(person => person.FirstName).NotNull();

但是我如何检查其中一个是否为空。

此外，是否可以在通过 fluentValidation 创建验证后，在客户端使用它来显示错误？

编辑1

    protected void Application_Start()
    {
        AreaRegistration.RegisterAllAreas();

        FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
        RouteConfig.RegisterRoutes(RouteTable.Routes);
        BundleConfig.RegisterBundles(BundleTable.Bundles);
        FluentValidationModelValidatorProvider.Configure();
    }
//creating validation
namespace WebApplication1.Models.CustomValidator
{
    public class PersonValidator:AbstractValidator<Person>
    {
        public PersonValidator()
        {
            RuleFor(m => m.FirstName).NotEmpty().When(m => string.IsNullOrEmpty(m.LastName)).WithMessage("*Either First Name or Last Name is required");
            RuleFor(m => m.LastName).NotEmpty().When(m => string.IsNullOrEmpty(m.FirstName)).WithMessage("*Either First Name or Last Name is required");
        }
    }

}
//model class
[Validator(typeof(PersonValidator))]
public class Person
{
    public Person()
    {
        InterestList = new List<string>();
    }
    public int Id { get; set; }
    public int ContactId { get; set; }
    [RequiredIfEmpty("LastName")]
    public string FirstName { get; set; }
    [RequiredIfEmpty("FirstName")]
    public string LastName { get; set; }
    public string EmailAddress { get; set; }
    public string Phone { get; set; }
    public string Country { get; set; }
    public List<string> InterestList { get; set; } 
}
//view
@model WebApplication1.Models.Person

<script src="@Url.Content("~/Scripts/jquery-1.8.2.min.js")"></script>
<script src="@Url.Content("~/Scripts/jquery.validate.min.js")"></script>
<script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")"></script>
<script src="@Url.Content("~/Scripts/jquery.unobtrusive-ajax.min.js")" type="text/javascript"></script>

@Html.ValidationSummary(true)
@using(Html.BeginForm("AddPerson","Person",FormMethod.Post))
{
    <div class="label">First Name</div>
    <div class="input-block-level">@Html.TextBoxFor(m=>m.FirstName)@Html.ValidationMessageFor(m=>m.FirstName)</div>
    <br/>
    <div class="label">Last Name</div>
    <div class="input-block-level">@Html.TextBoxFor(m=>m.LastName)@Html.ValidationMessageFor(m=>m.LastName)</div>
    <button type="submit" class="btn-primary">Submit</button>
}

Answer 1

您可以使用 When/Unless条件:

RuleFor(m => m.FirstName).NotEmpty().When(m => string.IsNullOrEmpty(m.LastName));
RuleFor(m => m.LastName).NotEmpty().When(m => string.IsNullOrEmpty(m.FirstName));

或

RuleFor(m => m.FirstName).NotEmpty().Unless(m => !string.IsNullOrEmpty(m.LastName));
RuleFor(m => m.LastName).NotEmpty().Unless(m => !string.IsNullOrEmpty(m.FirstName));

关于您的第二个问题，FluentValidation 适用于客户端验证，但并非所有规则都受支持。 Here您可以找到客户端支持的验证器:

1. NotNull/NotEmpty
2. 匹配(正则表达式)
3. InclusiveBetween(范围)
4. 信用卡
5. 电子邮件
6. EqualTo(跨属性相等比较)
7. 长度

对于不在列表中的规则，您必须编写自己的 FluentValidationPropertyValidator 并实现 GetClientValidationRules。您可以在 StackOverflow 上找到一些示例通过简单的搜索。