Question

I’m working on a site where users can add points to other user, however once a user added a point to other particular user he cannot add more points to the same user. So user1 can only give one point to user2.

On the server I check if there already exists a point with the same username. Everything works nicely so what I want to do now is to inform a user with some kind of message that he cannot add more points when he tries to do so since he already did add a point before. I think what i need is to return javascript from the server that will display the message. But maybe there is some other solution to this. Here is my action in controller:

[HttpPost]
    public ActionResult AddPointAndCopyCurrentFavToPlaylist(int id)
    {
        if (CheckIfPointExists(User.Identity.Name, id))
        {
        var originalSong = repository.GetCurrentFav(id);

        var newSong = new Song();
        newSong.UserName = User.Identity.Name;
        newSong.Title = originalSong.Title;
        newSong.YoutubeLink = originalSong.YoutubeLink;
        newSong.GenreId = 38;
        newSong.Date = DateTime.Now;
        repository.AddSong(newSong);

        var point = new Point();
        point.UsernameGotPoint = originalSong.UserName;
        point.UsernameGavePoint = User.Identity.Name;
        point.Date = DateTime.Now;
        point.Score = 1;
        point.CurrentFavId = id;
        repository.AddPoint(point);

        repository.Save();
        return RedirectToAction("Index");
        }
        else return JavaScript(???);
    }

here is my jquery Ajax:

  $(".btnAddOtherSongPoints").click(function () {
        var songId = $(this).attr("name");

        $.ajax({
            beforeSend: function () { ShowAjaxLoader(); },
            url: "/Home/AddPointAndCopyOtherSongToPlaylist/",
            type: "POST",
            data: { id: songId },
            success: function () { HideAjaxLoader(), ShowMsg("Song Added Successfully") },
            error: function () { HideAjaxLoader(), ShowMsg("Song could not be added, please try again") }
        });
    });

based on whether he was not allowed to give as point in the success part of my ajax request I want to display a different message so i’m guessing I would need an if statement in there to check whether the data object is not null (that means the server returned something, in this case a javascript function or something like that)

Answer 1

Well, when you return JavaScript from the controller, you are mixing ‘View’ functionality with ‘Controller’ functionality.

You could do this, but you’re going against convention & it may make it harder for the next developer on it to maintain.

Your Controller should only return data. You can check the data in your JavaScript for a success flag & display a message from there.

Edit:

In your controller:

    bool isSuccess = true;
   //process here
    return Json(new {Result = isSuccess}, JsonRequestBehavior.AllowGet);

In your JavaScript you check to see if Result == true.

Replace the success function in your $.ajax with something like this:

success: function (result) { 
   if (!result)
     { alert('Oh nooes'); }
},