Send messages from outside a hub

Question

User-1849651236 posted

Hello,

Has anyone been able to get this project to work?

I have tried it in Mozilla Firefox, Internet Explorer and Microsoft Edge.

I did not change any of the code.  I have tried clearing all my caches, cookies and temporary files.  I have tried restarting my system.

It looks like it is supposed to show "Home page loaded at: {DateTime.Now}".  I have not been able to see anything like that.

I would be interested in knowing if anyone else has made it work or if anyone has any idea of why it would not work.

Thanks,
Tony

Answer 1

User61956409 posted

Hi Tony,

I checked the sample code in github, and I find that there are not any hub methods defined in NotificationHub.

namespace SignalRNotify
{
    public class NotificationHub : Hub
    {
    }
}

You can refer to this documentation: "Use hubs in SignalR for ASP.NET Core" to create hub methods and send messages to clients.

With Regards,
Fei Han

Answer 2

User-1849651236 posted

Fei Han,

The title of this article is Send messages from outside a hub.  The tutorial is presented to show that it is possible to send messages from other places in your app using the IHubContext Service.

It also says: This article explains how to access a SignalR IHubContext to send notifications to clients from outside a hub.

Additionally, I have this Hub code in my application and it still displays the server to client messages:

using Microsoft.AspNetCore.SignalR;
using System.Threading.Tasks;

namespace  ChinavasionAPI.Hubs
{
     public class ChvHub : Hub
     {
          public async Task SendMessage(string user, string message)
          {
               //await Clients.All.SendAsync("ReceiveMessage", user, message);
          }
     }
}

That's the whole purpose of that article.

Somewhere I read that when the server is sending to a client, the Hub class does not need a method.  I will try to find that and post it here.

Added on 7/17/2018 12:45PM EDST

These articles talk about not needing a Hub Send method:

Github

StackOverflow

Thanks,
Tony