.net MVC 3 Request event - asp.net

Question

I am a little new to .net and trying to grasp a few concepts.
I have been writing in Coldfusion for a while, and in CF there is an event under the Application.cfc called onRequest() that fires each time there is a page.
What in .net is used to capture the request information?
And moreover is there a way to latch on or extend the Request event to fire off my own events?

Answer 1

You can also find global.asax file and use one of events of HttpApplication class (for example BeginRequest):
http://msdn.microsoft.com/en-us/library/system.web.httpapplication.aspx
HttpApplication has Request property.
You can catch every request there, not only related to Controller (images, css, wrong address).
public class MvcApplication : System.Web.HttpApplication
{
protected void Application_BeginRequest(object sender, EventArgs e)
{
//Request.Have_fun
}
}
If you don't want to write code in global.asax file, you should consider using HttpModule.
Create new class with this example code:
using System;
using System.Web;
namespace MyProject
{
public class MyHttpModule : IHttpModule
{
public void Init(HttpApplication application)
{
application.BeginRequest += ApplicationBeginRequest;
application.EndRequest += ApplicationEndRequest;
}
private void ApplicationEndRequest(object sender, EventArgs e)
{
//do something here with HttpContext.Current.Request
}
private static void ApplicationBeginRequest(Object source, EventArgs e)
{
//do something here with HttpContext.Current.Request
}
public void Dispose()
{
}
}
}
Add two entries in web.config (registers HttpModule):
<system.web>
<httpModules>
<add name="MyHttpModule" type="MyProject.MyHttpModule" />
</httpModules>
</system.web>
<system.webServer>
<modules runAllManagedModulesForAllRequests="true">
<add name="MyHttpModule" type="MyProject.MyHttpModule" />
</modules>
</system.webserver>
Because of changes in IIS7(adding system.webServer section), you have to add two entries in web.config.

Answer 2

You'll probably want something like OnActionExecuting which is called before the action is hit.
To access the current request you could do the following:
protected virtual void OnActionExecuting(ActionExecutingContext filterContext) {
//Do the default OnActionExecuting first.
base.OnActionExecuting(filterContext);
//The request variable will allow you to see information on the current request.
var request = filterContext.RequestContext.HttpRequest;
}
If you want to access this in every controller, then you should probably create a base controller and add this there.
public class BaseController : Controller
{
//Code above
}
And in your Home controller:
public class HomeController : BaseController
{
}

Answer 3

If you are working in ASP.NET MVC 3 I would recommend using global action filters (use one per "event" you want to handle) instead of tapping directly into the ASP.NET Application/Request stack.