了解ASP.NET MVC生命周期:为什么模型在ActionFilter中不可用? [英] Understanding ASP.NET MVC Lifecycle: Why is Model not available in ActionFilter?

问题描述

我创建了以下自定义ActionFilter，当我尝试在以下代码中访问 Model 时，它为null:

 公共类CustomPermissionCheckAttribute:ActionFilterAttribute{公共重写void OnActionExecuting(ActionExecutingContext context){OrganisationBaseController orgBaseController = context.Controller作为控制器；var vm =(((Controller)context.Controller).ViewData.Model as MyViewModel;//空值//检查当前用户是否具有vm.OrganisationId的权限base.OnActionExecuting(context);}} 

我试图理解为什么 Model 为null?根据

---

这是我注册上述动作过滤器的方式:

  [HttpPost][CustomPermissionCheck]公共ActionResult UpdateBranch(MyViewModel myViewModel){如果(ModelState.IsValid){//这样的事情}返回View();} 

解决方案

可以尝试使用此方法访问请求模型:

  MyViewModel vm = context.ActionParameters.Values.OfType< MyViewModel>().SingleOrDefault(); 

如何在操作过滤器中获取当前模型

I have created the following Custom ActionFilter, when I try to access the Model in the following code, it is null:

public class CustomPermissionCheckAttribute : ActionFilterAttribute
{
    public override void OnActionExecuting(ActionExecutingContext context)
    {
        OrganisationBaseController orgBaseController = context.Controller as Controller;
        var vm = ((Controller)context.Controller).ViewData.Model as MyViewModel; // null

        // check if current user has permission to vm.OrganisationId

        base.OnActionExecuting(context);
    }
}

I am trying to understand why the Model is null? According to ASP.NET MVC Lifecycle, ActionFilters are executed after Model Binder, so I am not sure why the Model is not available?

---

This is how I am register the above Action Filter:

[HttpPost]
[CustomPermissionCheck]
public ActionResult UpdateBranch(MyViewModel myViewModel)
{
    if (ModelState.IsValid)
    {
        // so something 
    }
    return View();
}

解决方案

Could try this to access the request model:

MyViewModel vm = context.ActionParameters.Values.OfType<MyViewModel>().SingleOrDefault();

How to get current model in action filter

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