Why is SignalR in asp.net c# with js client not working?

Question

ASP.NET

I did a similar thing in another project, it worked great. The bottom line: when you go to the MyData page, data is sent to the js client, it should display them

Now I have done everything according to this article https://metanit.com/sharp/aspnet5/30.6.php , I understand that everything should work, but no. There are no errors, the hub connection with the js client is established without problems, but no data is displayed.

controller

public class HomeController : Controller
    {
        private ApplicationDbContext _db;
        private IHubContext<MoexHub> _hub;
        public HomeController(ApplicationDbContext db, IHubContext<MoexHub> hub)
        {
            _db = db;
            _hub = hub;
        }



        public IActionResult Index()
        {
            return View();
        }

        public async Task<IActionResult> MyData()
        {
            await _hub.Clients.All.SendAsync("notify", "this is my message");
            return View();
        }
}

JS

const hubConnection = new signalR.HubConnectionBuilder()
    .withUrl("/chathub")
    .build();

// получение сообщения от сервера
hubConnection.on('notify', function (message) {

    // создает элемент <p> для сообщения пользователя
    let elem = document.createElement("p");
    elem.appendChild(document.createTextNode(message));

    document.getElementById("notify").appendChild(elem);

    console.log(message);

});
hubConnection.start();

VIEW Layout, namely how all files are connected
<div id="notify"></div>

<script src="~/lib/jquery/dist/jquery.min.js"></script>
    <script src="~/lib/signalr/dist/browser/signalr.min.js"></script>
    <script src="~/js/LoadData.js"></script>
    @await RenderSectionAsync("Scripts", required: false)
</body>
</html>

In startup, of course, I added everything, there are no errors.

Answer 1

The event name is case sensitive.
On the C# side you send "Notify" and on the js side you subscribe to "notify".
Change so that it matches on both sides.
Of course, there are no errors, because signalr does not know anything about what events the back and front can send.