复杂验证扩展

Question

在为Fluent验证规则构建器编写扩展时，我提出了进行更复杂的验证并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，等等。我所挣扎的是在多个领域的验证：

扩展方法作为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)); 
    } 

的MyRuleBuilder类允许添加规则流利：

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; 
    } 
} 

然后视图模型和查看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：

上述工作正常，但我不喜欢的是“If”功能。它不会强制所选属性类型的值。例如：

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 

这是可能的这种架构或我应采取不同的方法？

谢谢。

Answer 1

我认为你可以添加另一个通用参数U的方法。

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; 
    } 
}