MVC action names as constant string?

Question

I have the following code I have created to try and get rid of any magic strings related to MVC Action names. Potentially a dev could change the access mutator and access this in a page too.

private const string IndexAction = "Index";
public ActionResult Index(){
    //do stuff
}
public ActionResult Other(){
    // do stuff
    if(foo)
        return RedirectToAction(IndexAction);
    //don't foo
}

I have never seen this anywhere which leads me to that it is not a good idea and in the world of programming I doubt I am the first person to try this. Question: Is putting the name of the action bad practice does it break any principal of MVC.

Answer 1

What sometimes do is create an Enum with the action names in a given controller like so:

public class HomeController : Controller
{

    public enum Actions
    {
        Index,
        About,
        Contact,
        Hosting,
        Hartware
    } 

and I create an Extension method in and use the same namespace as the original class that I would like to extend, in this case I would use System.Web.Mvc and create the following class

namespace System.Web.Mvc
{
    public static class MvcExtentions
    {
        /// <summary>
        /// Generates a fully qualified URL to an action method by using the specified action Name.
        /// </summary>
        /// <param name="sender">used for the generate the logic</param>
        /// <param name="actionName">an enum that will be used to generate the name from</param>
        /// <returns>a fully qualified url to the action in the current controller</returns>
        public static string Action(this UrlHelper sender, Enum actionName)
        {
            return sender.Action(actionName.ToString());
        }
    }
}

Then in my Razor ViewPage add the Using to get to the in this case "HomeController" on the top of my page where ByteStream is the name of my project

@using ByteStream.Web.Controllers
@{
    ViewData["Title"] = "Home Page";
}

To generate the link I then use

<a class="btn btn-default btn-default" ref="@Url.Action(HomeController.Actions.Hosting))">
 Learn More
</a>

Answer 2

The nameof feature in C# allows you to do this easily. Your RedirectToAction call would look like this:

return RedirectToAction(nameof(Index));

nameof(Index) returns the string "Index". If you accidently change the name of the Index function, then this line would produce a compiler error. Plus doing a rename refactor on Index would change this too, and a Find All References command would point to it as well. But if you want to redirect to a method in a different controller, then this would not work so well.