Question

I have an interesting problem with the TempData object not passing values to another controller.

I set TempData["Enroll"] in the Enroll Controller‘s HttpPost method to an Enroll Model. I then read the TempData["Enroll"] object in the Register Controller‘s HttpGet method, but is empty/null.

I need to persist all of this data across 3 controllers.

Any thoughts?

Here is a code Snippet

//EnrollController.cs
[HttpPost]
public ActionResult Index(EnrollModel model)
{
   // ...
   TempData["EnrollModel"] = model;
   return RedirectToAction("Index", "Register");
}

// RegisterController.cs
public ActionResult Index(string type)
{
    RegisterModel model = new RegisterModel();

    EnrollModel enrollModel = TempData["EnrollModel"] as EnrollModel;
    model.ClientType = enrollModel.ClientType;
    // ...
}

Answer 1

I have come across these sorts of limitations with TempData before. I found it unrealiable and sporadic at best.

You need to consider what you are trying to achieve. If you do need to store data, in practice the best place to do this is in a db (or store of sorts) it might seem a bit overkill but that is their purpose.

Two other points:

1. Someone can hit your RegisterController Index method without going to the other before, in which case your code would break.

2. If you are doing a multiple wizard style process, why not store the data in its partial state in the db, and complete the process only on the last screen? In this way no matter, where they stop/start or pick it up again, you will always know where they are in the process.