如何在请求过滤器中的 ViewResult 上设置视图模型？

Posted 2023-02-27

【中文标题】如何在请求过滤器中的 ViewResult 上设置视图模型？

【英文标题】：How to set view model on ViewResult in request filter?

【发布时间】：2013-12-01 07:19:37

【问题描述】：

我做了一个 MVC 项目，我想从过滤器中将模型设置为视图。

但我不知道，我该怎么做。

模型：

public class TestModel

    public int ID  get; set; 
    public string Name  get; set; 

控制器：

[CustomFilter(View = "../Test/Test")]//<===/Test/Test.cshtml
public ActionResult Test(TestModel testModel)//<===Model from Page

      //the Model has Value!!
       // if has some exception here
        return View(model);//<=====/Test/Test.cshtml

过滤器（只是演示）：

public override void OnActionExecuting(ActionExecutingContext filterContext)
     ViewResult vr = new System.Web.Mvc.ViewResult()
     
            ViewName = this.View,//<======/Test/Test.cshtml
            ViewData = filterContext.Controller.ViewData                             
      ;
      //How can I set Model here?!!
      vr.Model = ???? //<========the Model is only get
      filterContext.Result = vr;

编辑开始感谢@Richard Szalay @Zabavsky @James @spaceman

更改过滤器扩展到 HandleErrorAttribute

  ViewResult vr = new System.Web.Mvc.ViewResult()
     
            ViewName = this.View,//<======/Test/Test.cshtml
            ViewData = new ViewDataDictionary(filterContext.Controller.ViewData)
            
                //I want get testModel from Action's paramater
                //the filter extends HandleErrorAttribute
                Model = new  ID = 3, Name = "test" // set the model
                                         
      ;

编辑结束

测试/Test.chtml

@model TestModel
<h2>Test</h2>
@Model //<=====model is null

当我请求时

http://localhost/Test/Test?ID=3&Name=4

测试页无法获取模型。

【参考方案1】：

模型属性实际上只是一个 ViewDataDictionary，您可以使用您的实际模型初始化它的实例，即

vr.Model = new ViewDataDictionary(model);

【讨论】：

也非常感谢。

【参考方案2】：

ViewResult vr = new System.Web.Mvc.ViewResult
    
        ViewName = this.View, //<======/Test/Test.cshtml
        ViewData = new ViewDataDictionary(filterContext.Controller.ViewData)
            
                Model = // set the model
            
    ;

【讨论】：

非常感谢，我也想知道，在 filter Model = testModel

@zt9788, OnActionExecuting 在动作之前运行，你还没有任何模型。

如果过滤器扩展了 HandleErrorAttribute 并且异常在 Action 中抛出。能拿到Model吗？

【参考方案3】：

来自 asp.net mvc 源，他们只是在视图数据中设置模型。 http://aspnetwebstack.codeplex.com/SourceControl/latest#src/System.Web.Mvc/Controller.cs

 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,
            ViewEngineCollection = ViewEngineCollection
        ;
    

【参考方案4】：

您可以修改过滤器上下文，并设置视图、模型、视图数据以及您想要的任何内容。您必须考虑一些事情：

// You can specify a model, and some extra info, like ViewBag:
ViewDataDictionary viewData = new ViewDataDictionary

    Model = new MyViewModel
    
        ModelProperty = ...,
        OtherModelProperty = ...,
        ...
     
;

// You can take into account if it's a partial or not, to return a View 
// or Partial View (casted to base, to set the remaining data):
ViewResultBase result = filterContext.IsChildAction
    ? new PartialViewResult()
    : (ViewResultBase) (new ViewResult());

// Set the remaining data: Name of the View, (if in Shared folder) or
// Relative path to the view file with extension, like "~/Views/Misc/AView.cshtml"
result.ViewName = View;                     
result.ViewData = viewData;     // as defined above

// Set this as the result
filterContext.Result = result;  

这样，您的视图将根据需要接收模型。

【参考方案5】：

你可以从 filtercontext 中获取控制器，然后在控制器上使用 View 方法，像这样：

filterContext.Result = (filterContext.Controller as Controller).View(model);