c# - 复杂验证扩展

Question

在为 Fluent Validation 规则构建器编写扩展时，我想到了进行更复杂的验证然后将其与客户端验证连接起来的想法。我已经成功创建了基于另一个属性验证一个属性的扩展，依此类推。我正在努力解决的是对多个字段的验证:

扩展方法如https://fluentvalidation.codeplex.com/wikipage?title=Custom&referringTitle=Documentation

public static IRuleBuilderOptions<T, TProperty> Required<T, TProperty>(this IRuleBuilder<T, TProperty> ruleBuilder, Action<MyRuleBuilder<T>> configurator)
    {
        MyRuleBuilder<T> builder = new MyRuleBuilder<T>();

        configurator(builder);

        return ruleBuilder.SetValidator(new MyValidator<T>(builder));
    }

允许流畅添加规则的 MyRuleBuilder 类:

public class MyRuleBuilder<T>
{
    public Dictionary<string, object> Rules = new Dictionary<string,object>();

    public MyRuleBuilder<T> If(Expression<Func<T, object>> exp, object value)
    {
        Rules.Add(exp.GetMember().Name, value);

        return this;
    }
}

然后 View 模型和 View 模型验证器规则如下所示:

public class TestViewModel
{
    public bool DeviceReadAccess { get; set; }
    public string DeviceReadWriteAccess { get; set; }
    public int DeviceEncrypted { get ; set; }
}

RuleFor(x => x.HasAgreedToTerms)
    .Required(builder => builder
        .If(x => x.DeviceReadAccess, true)
        .If(x => x.DeviceReadWriteAccess, "yes")
        .If(x => x.DeviceEncrypted, 1 ));

问题:

上面的代码工作正常，但我不喜欢的是“If”函数。它不强制该值属于选定的属性类型。示例:

RuleFor(x => x.HasAgreedToTerms)
    .Required(builder => builder
        .If(x => x.DeviceReadAccess, true) // I would like the value to be enforced to bool
        .If(x => x.DeviceReadWriteAccess, "yes") // I would like the value to be enforced to string

// Ideally something like 

// public MyRuleBuilder<T> If(Expression<Func<T, U>> exp, U value) but unfortunately U cannot be automatically inferred

这种架构是否可行，还是我应该采用不同的方法？

谢谢。

Answer 1

我认为您可以向该方法添加另一个通用参数U。

public class MyRuleBuilder<T>
{
    public Dictionary<string, object> Rules = new Dictionary<string, object>();

    public MyRuleBuilder<T> If<U>(Expression<Func<T, U>> exp, U value)
    {
        Rules.Add(exp.GetMember().Name, value);

        return this;
    }
}