根据 ASP.NET 核心中的控制器有条件要求

Question

我想写条件要求，但条件取决于使用它的控制器。

我已经有自定义属性 MyRequiredIfNot。我只是不知道如何在 IsValid 方法中获取有关控制器的信息。

例如：

public class MyController1 : Controller
{
    public ActionResult Method1(MyModel model)
    { 
      //Name is required !!!
    }
}

public class MyController2 : MyController1 
{
    public ActionResult SomeMethod(MyModel model)
    { 
       //Name is NOT required !!!
    }
}

public class MyModel
{
    [MyRequiredIfNot(MyController2)
    public string Name { get;set; }
}

缺少实现：

public class MyRequiredIfNotAttribute : ValidationAttribute
{
    public MyRequiredIfNotAttribute(Controller controller) { }

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        if (/*came_from ?*/ is this.controller)          //Missing !!!!
            return ValidationResult.Success;
        else
            return base.IsValid(value, validationContext);
    }
}

Answer 1

要检索 Controller，您可以尝试 IActionContextAccessor。

按照以下步骤操作：

注册IActionContextAccessor

public void ConfigureServices(IServiceCollection services)
{

    services.AddSingleton<IActionContextAccessor, ActionContextAccessor>();

    //rest services
}

MyRequiredIfNotAttribute

public class MyRequiredIfNotAttribute : RequiredAttribute//ValidationAttribute
{
    private Type _type;
    public MyRequiredIfNotAttribute(Type type) {
        _type = type;
    }

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        var actionContext = validationContext.GetRequiredService<IActionContextAccessor>();
        var controllerActionDescriptor = actionContext.ActionContext.ActionDescriptor as ControllerActionDescriptor;
        var controllerTypeName = controllerActionDescriptor.ControllerTypeInfo.FullName;
        if (_type.FullName == controllerTypeName)
        {
            return ValidationResult.Success;
        }
        else
        {
            return base.IsValid(value, validationContext);
        }            
    }
}

用法

public class MyModel
{
    [MyRequiredIfNot(typeof(MyController))]
    public string Name { get; set; }
}

根据 ASP.NET 核心中的控制器有条件要求

Conditional required based on Controller in ASP.NET Core

c#

model-binding

asp.net-core-mvc

asp.net-core