Redirect to Action from within a method

Question

In most of the Actions in my controller I need to check to see if a condition has been meet, and if not redirect the user to another Action in the same controller so I tried:

    public ActionResult Transactions()
    {
        GrossGalsConfermation();
        return View();
    }

    public void GrossGalsConfermation()
    {
        if (Session["HasConfirmed"] == null && TerminalUserData.IsGrossGallonTerminal)
        {
            RedirectToAction("ConversionFactors");
        }
    }

but even when the if statement is true the RedirectToAction is not executed. I have done a debug in VS and can see it jump from the Action to the Method, evaluate the IF statement and go into it to run the RedirectToAction but then it jumps right back to the calling Acation and return's it's view. How can I force it to redirect? Searching on line I find similar problems and the solution was to change from void to ActionResult but then I have to provide an fallback Action to return which can not be done since this Method will be called by dozens of views.

Answer 1

All RedirectToAction does is return a RedirectToRouteResult - the browser won't be redirected unless you actually return it. Since you don't want to do this within your method (you could return null and do null checks in your action but it would be clumsy), I'd suggest using an action filter instead. Something like the following would do it:

public class GrossGalsFilterAttribute : ActionFilterAttribute
{
    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        if (Session["HasConfirmed"] == null
                                    && TerminalUserData.IsGrossGallonTerminal)
        {
            filterContext.Result =
                new RedirectToRouteResult(new RouteValueDictionary(new
                { controller = "MyController", action = "ConversionFactors" }));
        }

        base.OnActionExecuting(filterContext);
    }
}

Then decorate your controller actions:

[GrossGalsFilter]
public ActionResult MyControllerAction

Note that you may have to modify the filter to get hold of TerminalUserData.IsGrossGallonTerminal - impossible to know where this comes from based on your question.

More on action filters: http://msdn.microsoft.com/en-us/library/dd381609(v=vs.100).aspx

Answer 2

You are missing a "return":

return RedirectToAction(...);

If you want to reuse the method multiple times you should look into writing a filter.