Question

I am using MVC4 and I have a question, rather than declaring ViewBag.MenuLevel=”twostage”; in EACH ActionResult in my controllers can I declare it ONCE for each controller somehow? Right now for example I have lets say 40 ActionResults per controller, this seems silly to have to declare a variable that many times – so I am sure I am missing something simple.

I need to be able to consume it in my View somehow to affect presentation. Thoughts? Models? Kind of new to MVC so be gentle! 😉

Basically I want each section (controller) to display a different background-color on the front-end so I want to print the section/controller to an id in the html so I can control via css.

Cheers.

Answer 1

You are going to have to set the ViewBag data each time, that’s an unavoidable feature of the architecture. However, you can make it a little cleaner in terms of controller code with an attribute applied to the controller.

public class ViewBagAttribute : ActionFilterAttribute
{
    public void OnActionExecuting(ActionExecutingContext filterContext)
    {
        var controller = filterContext.Controller;

        controller.ViewBag.MenuLevel = "twostage";
    }

    public void OnActionExecuted(ActionExecutedContext filterContext) { }
}

If you apply that attribute to the controller, you won’t have to explicitly add the ViewBag code for each Action method, as OnActionExecuting is called automatically for every Action method.