Why does JsonResult produce 500 internal server error?

Question

I am trying to retrieve a value from my Microsoft SQL Server database. It is a nullable "bit".

The code to retrieve

[HttpGet]
public JsonResult WishesVisit()
{
    int firmaid = SessionExtensions.GetFirmaId(Session);
    var firma = db.Firma.Where(x => x.firma_id == firmaid).FirstOrDefault();

    if (firma != null)
    {
        if (firma.oensker_besog != null)
        {
            if ((bool)firma.oensker_besog)
            {
                return Json("true");
            }
            else
            {
                return Json("false");
            }
        }
    }

    return Json("null"); 
}

And the code to retrieve:

$.getJSON('WishesVisit', function (data) {
    alert(data);
});

Why am i getting a 500 internal server error?

The debugger doesn't catch any exception.

Answer 1

The problem is most likely because ASP.NET MVC does not allow JSON requests using GET by default. You can add JsonRequestBehavior.AllowGet as a second parameter to your Json call:

return Json("true", JsonRequestBehavior.AllowGet);

If not, can you provide a error message?