如何在ActionFilter

Question

我尝试创建自定义操作过滤器，执行验证并根据结果创建自定义视图。执行操作过滤器时，它仅显示文本：<h2>My View</h2>（不使用布局）。我还试图覆盖 OnResultExecuting 方法并在那里设置主名称（filterContext.Result as ViewResult）.MasterName =＆＃34; Layout＆＃34; ，但是结果仍然相同。那么可以设置布局吗？

public class MyValidationFilterAttribute : ActionFilterAttribute
{
    public string Layout { get; set; }

    public MyValidationFilterAttribute(string layout = "_Layout")
    {
        Layout = layout;
    }

    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        var result = TodoValidate();
        if (!result)
            filterContext.Result = new ViewResult() { View = new MyView(), MasterName = Layout};

        base.OnActionExecuting(filterContext);
    }        
}

public class MyView : IView
{
    public void Render(ViewContext viewContext, TextWriter writer)
    {
        writer.Write("<h2>My View</h2>");
    }
}

//更新1：

基于ASP.NET MVC源代码，当 View！= null 时，忽略 MasterName 。所以我认为如果我想使用 IVIew 我不能重复使用Layout，但我必须手动渲染整个html页面。

// ----------------
//ViewResult.cs
// ----------------

// FindView is called from ViewResultBase class only when the View == null
protected override ViewEngineResult FindView(ControllerContext context)
{
  ViewEngineResult view = this.ViewEngineCollection.FindView(context, this.ViewName, this.MasterName);
  if (view.View != null)
    return view;
  // rest of the code
}

// ----------------
// ViewResultBase.cs
// ----------------
public override void ExecuteResult(ControllerContext context)
{
  if (context == null)
    throw new ArgumentNullException("context");
  if (string.IsNullOrEmpty(this.ViewName))
    this.ViewName = context.RouteData.GetRequiredString("action");
  ViewEngineResult viewEngineResult = (ViewEngineResult) null;
  if (this.View == null)
  {
    viewEngineResult = this.FindView(context);
    this.View = viewEngineResult.View;
  }
  TextWriter output = context.HttpContext.Response.Output;
  this.View.Render(new ViewContext(context, this.View, this.ViewData, this.TempData, output), output);
  if (viewEngineResult == null)
    return;
  viewEngineResult.ViewEngine.ReleaseView(context, this.View);
}