Question

我有一个继承自基本控制器的控制器，我想知道如何利用基本控制器的所有逻辑，但返回的视图与基本控制器使用的不同。

基本控制器填充模型对象并将该模型对象传递给其视图，但我不确定如何在子控制器中访问该模型对象，以便将其传递给子控制器的视图。

Answer 1

几点。如果您知道所有要返回的内容，则可以将返回值键入ViewResult。然后，您可以从重写的实现中查询该值。更重要的是，根据MVC v1源代码，调用View（object）只需在控制器上设置ViewData.Model，然后构造一个ViewResult。

Controller.cs：440

protected internal ViewResult View(object model) {
    return View(null /* viewName */, null /* masterName */, model);
}

Controller.cs：456

protected internal virtual ViewResult View(string viewName, string masterName, object model) {
    if (model != null) {
        ViewData.Model = model;
    }

    return new ViewResult {
        ViewName = viewName,
        MasterName = masterName,
        ViewData = ViewData,
        TempData = TempData
    };
}

所以你需要做的就是调用base方法并调用View（string）。

namespace BaseControllers
{
    public class CoolController
    {
        public virtual ViewResult Get() 
        {
            var awesomeModel = new object();
            return View(awesomeModel);
        }
    }
}

public class CoolController : BaseControllers.CoolController
{
    public override ViewResult Get() 
    {
        var ignoredResult = base.Get();
        // ViewData.Model now refers to awesomeModel
        return View("NotGet");
    }
}

当然，您浪费了CPU周期来构建您忽略的ViewResult。所以你可以这样做：

public class CoolController : BaseControllers.CoolController
{
    public override ViewResult Get() 
    {
        var baseResult = base.Get();
        baseResult.ViewName = "NotGet";
        return baseResult;
    }
}

如果您的基本控制器返回ActionResult，则必须在更改ViewName之前将其强制转换为ViewResult。

Answer 2

来自我的应用的示例：

基类：

public abstract class BaseTableController<T,TU> : BaseController where TU : IGenericService<T>,IModelWrapperService
{
    protected readonly TU _service;

    public BaseTableController(TU service)
    {
        _service = service;
        _service.ModelWrapper = new ControllerModelStateWrapper(ModelState);
    }


    public ActionResult Index()
    {
        return View(_service.List());
    }

<强>继承：

public class SeverityController : BaseTableController<Severity, ISeverityService>
{
    public SeverityController(ISeverityService service)
        : base(service)
    {
    }

   //NO CODE INSIDE
}

SeverityController.Index（）导致Views / Severity / Index.aspx。只需要准备视图。严重性是我的错误跟踪应用程序中的一个词典。每个字典都有类似的逻辑，所以我可以分享一些代码。

Answer 3

根据此主题提供的反馈，我实施了一个类似于Antony Koch提出的解决方案。

我没有使用抽象方法，而是使用了一个具体的虚拟GetIndex方法，以便我可以为基本控制器输入逻辑。

public class SalesController : Controller
{
    // Index view method and model
    public virtual ActionResult GetIndex()
    {
         return View("Index", IndexModel);
    }
    protected TestModel IndexModel { get; set; }

    public virtual ActionResult Index()
    {
        ViewData["test"] = "Set in base.";

        IndexModel = new TestModel();
        IndexModel.Text = "123";

        return GetIndex();
    }

    [AcceptVerbs(HttpVerbs.Post)]
    public virtual ActionResult Index(TestModel data, FormCollection form)
    {
        TryUpdateModel(data, form.ToValueProvider());
        IndexModel = data;

        return GetIndex();
    }
}

// This class will need to be in a different namespace or named differently than the
// parent controller
public class SalesController : MyApp.Controllers.BaseControllers.SalesController
{
    // Index view method and model
    public override ActionResult GetIndex()
    {
        return View("ClientIndex", IndexModel);
    }

    public override ActionResult Index()
    {
        return base.Index();
    }

    [AcceptVerbs(HttpVerbs.Post)]
    public override ActionResult Index(TestModel data, FormCollection form)
    {
        return base.Index(data, form);
    }
}

Answer 4

我最后只在基础控制器上添加了一个额外的参数 - viewName。

似乎工作正常。

我是否遗漏了任何重大缺点？

public class SalesController : Controller
{
    public virtual ActionResult Index(string viewName)
    {
        ViewData["test"] = "Set in base.";

        TestModel model = new TestModel();
        model.Text = "123";

        return String.IsNullOrEmpty(viewName) ? View(model) : View(viewName, model);
    }

    [AcceptVerbs(HttpVerbs.Post)]
    public virtual ActionResult Index(TestModel data, FormCollection form, string viewName)
    {
        TryUpdateModel(data, form.ToValueProvider());
        return String.IsNullOrEmpty(viewName) ? View(data) : View(viewName, data);
    }
}

public class SalesController : MyApp.Controllers.BaseControllers.SalesController
{
    public override ActionResult Index(string viewName)
    {
        return base.Index("ClientIndex");
    }

    [AcceptVerbs(HttpVerbs.Post)]
    public override ActionResult Index(TestModel data, FormCollection form, string viewName)
    {
        return base.Index(data, form, "ClientIndex");
    }
}

Answer 5

public class BaseController : Controller {
protected BaseController() {}

public ActionResult Index()
{
    return GetIndex();
}

public abstract ActionResult GetIndex();  }

public class MyController : BaseController {
public MyController() {}

public override GetIndex()
{   
    return RedirectToAction("Cakes","Pies");
}

}

只需使用抽象来从子类中调用所需的位。

如何继承ASP.NET MVC控制器并仅更改视图？

5 个答案: