如何为我的 asp.net MVC 站点的每个访问者添加 cookie？

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.

Answer 2

This would work regardless of what page the user first comes in at. You could inherit your controllers with a base controller and then add some information to the OnActionExecuting method

public class BaseController : Controller
{
    protected override void OnActionExecuting(ActionExecutingContext context)
    {
        HttpCookie myCookie = Request.Cookies[keyOfSomeKind];

        if (myCookie == null)
        {
            HttpCookie newCookie
                = new HttpCookie(keyOfSomeKindy, "Some message");
            newCookie.Expires = DateTime.Now.AddMinutes(3);
            current.Response.Cookies.Add(newCookie);
        }

        base.OnActionExecuting(context);
    }
}

Answer 3

You already have session and the session cookie.

But if you need to write a specific value to a cookie you have access to the response stream from the controller

this.Response.Cookies.Add(); inside the controller (this isn't required)

Answer 4

Setting a cookie should be done in your controller. You can set a cookie like so:

Response.Cookies.Add(new HttpCookie(cookieName, cookieValue));

If you need to get the value in your view, the best way would be to fetch it in your controller and stick it in a view model or viewstate:

var cookie = Response.Cookies[cookieName];
ViewData["CookieInfo"] = cookie.Value;

And in your view:

@ViewData["CookieInfo"]