When exactly do OnResultExecuted and OnResultExecuting fire?

Question

I'm creating a custom ActionFilterAttribute in order to transform ViewResults and redirects into JsonResults during ajax requests. I've wired most of it through unit testing and I was for some reason assuming my transformation had to take place in OnResultExecuting, I realized this was not the case, and the correct method to override was OnActionExecuted, which is called as soon as the action method returns a result.

My question is when exactly are OnResultExecuted and OnResultExecuting being called since I've breakpoints in all four overrides and only the ones in OnActionExecuting and OnActionExecuted are firing at all.

Answer 1

Let's take the following example which performs the transformation you described:

public class MyActionFilterAttribute : ActionFilterAttribute {     public override void OnActionExecuted(ActionExecutedContext filterContext)     {         if (filterContext.HttpContext.Request.IsAjaxRequest())         {             var result = filterContext.Result as ViewResultBase;             if (result != null && result.Model != null)             {                 filterContext.Result = new JsonResult                 {                     Data = result.Model,                     JsonRequestBehavior = JsonRequestBehavior.AllowGet                 };             }         }     }      public override void OnResultExecuting(ResultExecutingContext filterContext)     {     }      public override void OnResultExecuted(ResultExecutedContext filterContext)     {     } } 

The OnResultExecuting method will be invoked immediately before the action result's ExecuteResult method runs and the OnResultExecuted method immediately after.

Answer 2

After looking for a while and trying to understand the accepted answer I found this. I believe this shows the order of Execution to be

1. OnActionExecuting
2. OnActionExecuted
3. OnResultExecuting
4. OnResultExecuted

Check this link under listing 2. http://www.asp.net/mvc/overview/older-versions-1/controllers-and-routing/understanding-action-filters-cs