Question

I’m experimenting with an ASP.NET MVC 3 site, using razor as the view-engine. I need to assign a cookie to every visitor of my site. What would be the best place/way to do this?
Please elaborate, because I’m very new at ASP.NET.

Answer 1

There are 3 ways to implement it without breaking mvc pattern:

1 – Base controller class with specified behaviour at OnActionExecuting / OnActionExecuted / OnResultExecuting method (if this behavior is necessary across the entire web site)

2 – Create action filter with specified behaviour at OnActionExecuting / OnActionExecuted / OnResultExecuting methods:

public class MyCookieSettingFilterAttribute : ActionFilterAttribute 
{
    public override void OnActionExecuted(ActionExecutedContext filterContext)
    {
        filterContext.HttpContext.Response.Cookies.Add(new HttpCookie(name, value));
    }
}

and

assign filter attribute to some controllers/actions (if this behavior is not necessary for all web site), for example

[MyCookieSettingFilter]
public class MyHomeController : Controller
{
}

or

public class MyAccountController : Controller
{
    [MyCookieSettingFilter]
    public ActionResult Login()
    {
    }
}

3 – Create action filter with specified behaviour at OnActionExecuting / OnActionExecuted / OnResultExecuting methods and register it at global.asax – it will work for all actions of all controllers (if this behavior is necessary for all web site)

public static void RegisterGlobalFilters(GlobalFilterCollection filters)
{
   filters.Add(new MyCookieSettingFilterAttribute());
}

I don’t recommend to use Base Controller way, because it less extensible than Global Filter way. Use different global filters for providing different independent global behaviors.