Visual Studio 2012 - Variable missing from Locals Window

Question

I have never seen this before and have no idea what it causing it.

When I put a breakpoint at the end of code below, the elapsedSeconds variable is NOT listed in the locals window. If I try to Watch it, the Value = "The name 'elapsedSeconds' does not exist in the current context". How is that possible???

public ActionResult Index()
{
    Stopwatch sw = Stopwatch.StartNew();

    var userID = WebSecurity.GetUserId(User.Identity.Name);

    var model = ModelHelper.GetModel(userID);

    long elapsedSeconds = 0;
    elapsedSeconds = sw.ElapsedMilliseconds;

    return View(model);
}

Answer 1

Select 'Code Optimization' property as "Disabled" in Project property window, in case you want to take a look at the value. It's the compiler optimization process, that renders evaluating that variable unnecessary.