ASP.NET MVC with Action Filters

Introduction: While developing an ASP.NET MVC application, you may require the ability to apply various filters which work as restrictions to the controller as per the requirement of the user.

Steps to use Action Filter in an application  

Step 1: Open Visual Studio 2010

 

• Click on new from the menu strip
• Choose project
   

 

• Now click on ASP.NET MVC empty application from the installed template

Step 2: Add a controller in which we can apply action filter 

• Right click on the controllers folder
  
• Choose to Add controller

 

• And name the contoller
   

 

Action Filter which cached the value for 5 seconds.

Code for the Controller

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;

namespace MvcApplication13.Controllers
{
   {
     [OutputCache(Duration=5)]
       public string Index()
        {
          return DateTime.Now.ToString("T");
          }
      }
 }

ASP.NET MVC provide an interesting feature to deal with filters i.e it allows the user to use custom filters like:
1. Authorization Filters - This filter implements the IAuthorizationFilter as Attribute.
2. Action Filters - This filter implements the IActionFilter as attribute.
3. Result Filters - This filter implements the IResultFilter as attribute.
4. Exception Filter - This filter implements the IExceptionFilter as attribute.

Step 3: Now next step is to use a custom filter; we can create Log Action Filter
This Log Action Filter is an custom action filter that will provide a brief description about execution 

• For this purpose create a new model class > right click on the model folder >  add class

 

Code for this step will be :

using System;
using System.Diagnostics;
using System.Web.Mvc;
using System.Web.Routing; 

namespace MvcApplication13.ActionFilters
{
     public class LogActionFilter : ActionFilterAttribute
     {
          public override void OnActionExecuting(ActionExecutingContext filterContext)
          {
               Log("OnActionExecuting", filterContext.RouteData);      
          }
          public override void OnActionExecuted(ActionExecutedContext filterContext)
          {
               Log("OnActionExecuted", filterContext.RouteData);      
          }
          public override void OnResultExecuting(ResultExecutingContext filterContext)
          {  
             Log("OnResultExecuting", filterContext.RouteData);      
          }
          public override void OnResultExecuted(ResultExecutedContext filterContext)
          {
           Log("OnResultExecuted", filterContext.RouteData);      
           }
           private void Log(string methodName, RouteData routeData)
           {
           var controllerName = routeData.Values["controller"];
           var actionName = routeData.Values["action"];
           var message = String.Format("{0} controller:{1} action:{2}", methodName, controllerName, actionName);
           Debug.WriteLine(message, "Action Filter Log");
           }
               }
                    }

Step 4: Now with a reference to the model class add a controller to it to get the view from action method
 

 

Now code the controller to use the LogActionFilter
 

using System.Web.Mvc;
using MvcApplication13.ActionFilters;
namespace MvcApplication13.Controllers
{
     [LogActionFilter]
     public class PacificController : Controller
     {
      public ActionResult Index()
     {
      return View();
      }
      public ActionResult About()
      {
      return View();
      }
    }
  }

Output:

 

Summary - We can use Action Filters as well as Custom Filters in ASP.NET MVC Application as per user's requirements.