Asp.net mvc: Posting Back from the View

Question

Is it considered better practice to post back to the same controller that did the rendering and redirecting from original controller if necessary? Or is it just the same if one jumps to different controllers from the view?

Answer 1

I think that the action that is being called should be contained within a relevant controller for that action. If the view needs to call the action it should call it from the relevant controller, not necessarily the controller that it was spawned from.

If you have an inventory controller you don't want to define actions that relate to administration even if an inventory screen might have an administration action on it, as an example.

Answer 2

I create two overloaded actions in the controller, one to render the input form using an HTTP GET and the other to process the form post using an HTTP POST. Something like this:

  public ViewResult Foo()
  {
    return View();
  }

  [AcceptVerbs(HttpVerbs.Post)]
  public ViewResult Foo( FormCollection form )
  {
    // process input
    if (inputOK)
      return RedirectToAction("Index");
    return View();
  }

The benefit of doing it this way is that if there's an error, the view gets re-rendered with any error and validation messages. If it's successful, there's a redirect to another action, which avoids the duplicate posting warning on browsers if a user refreshes the page - see Post/Redirect/Get on Wikipedia and this blog entry by Stephen Walther.

There are alternatives to taking a FormCollection, e.g. a list of simple parameters or binding to an object. See this article by ScottGu.