SignalR .Net client: How do I send a message to a

2019-03-09 11:01发布

问题:

I am using the sample Chat application from the SignalR Wiki Getting Started Hubs page. I have extended it to add Group support and it is working fine.

However, now I want to send a message to the group from an external Console application. Here is my code for the Console app and below that my code for Groups. How do I send a message to a Group from a proxy? Is it possible?

// Console App
using System;
using Microsoft.AspNet.SignalR.Client.Hubs;

namespace SignalrNetClient
{
    class Program
    {
        static void Main(string[] args)
        {
            // Connect to the service
            var connection = new HubConnection("http://localhost:50116");
            var chatHub = connection.CreateHubProxy("Chat");

            // Print the message when it comes in
            connection.Received += data => Console.WriteLine(data);

            // Start the connection
            connection.Start().Wait();

            chatHub.Invoke("Send", "Hey there!");

            string line = null;
            while ((line = Console.ReadLine()) != null)
            {
                // Send a message to the server
                connection.Send(line).Wait();
            }
        }
    }
}

SignalR Web App Host:

namespace SignalrServer.Hubs
{
    public class Chat : Hub
    {
        public void Send(string message)
        {
            // Call the addMessage method on all clients            
            Clients.All.addMessage(message);
            Clients.Group("RoomA").addMessage("Group Message " + message);
        }

        //server
        public void Join(string groupName)
        {
            Groups.Add(Context.ConnectionId, groupName);
        }
    }
}

Default.aspx

<script src="http://code.jquery.com/jquery-1.8.2.min.js" type="text/javascript"></script>
<script src="Scripts/jquery.signalR-1.0.1.min.js" type="text/javascript"></script>
<!--  If this is an MVC project then use the following -->
<!--  <script src="~/signalr/hubs" type="text/javascript"></script> -->
<script src="signalr/hubs" type="text/javascript"></script>
<script type="text/javascript">
    $(function () {
        // Proxy created on the fly          
        var chat = $.connection.chat;

        // Declare a function on the chat hub so the server can invoke it          
        chat.client.addMessage = function (message) {
            $('#messages').append('<li>' + message + '</li>');
        };

        $.connection.hub.start(function () {
            chat.server.join("RoomA");
        });

        // Start the connection
        $.connection.hub.start().done(function () {

            $("#broadcast").click(function () {
                // Call the chat method on the server
                chat.server.send($('#msg').val());
            });
        });
    });
</script>

  <div>
    <input type="text" id="msg" />
<input type="button" id="broadcast" value="broadcast" />

<ul id="messages">
</ul>
  </div>

回答1:

What I have done with something similar is to create a method which accepts an object of your choice, e.g.

Your new class

public class MyMessage{
    public string Msg { get; set; }
    public string Group { get; set; }
}

Then create a method in the Hub that accepts this object.

public void Send(MyMessage message)
{
    // Call the addMessage method on all clients            
    Clients.All.addMessage(message.Msg);
    Clients.Group(message.Group).addMessage("Group Message " + message.Msg);
}

Then from your client, you can then pass this object in.

chatHub.Invoke<MyMessage>("send", new MyMessage() { Msg = "Hello World", Group = "RoomA" });

You can then also call this from the JS client

chat.server.send({ Msg: "Hello World", Group: "RoomA" });


回答2:

In Winform .Net framework 4.0 the group doesn't work any more.

Server Code:

[HubName("PublicHub")]
public class PublicHub : HubBase
{
    /// <summary>
    /// join group
    /// </summary>
    /// <param name="userLoginName"></param>
    /// <param name="hotelId"></param>
    /// <param name="groupCode"></param>
    [HubMethodName("JoinGroup")]
    public async Task JoinGroupAsync(string userLoginName, string hotelId, string groupCode)
    {
        await Groups.Add(Context.ConnectionId, ShopGroupKey(hotelId, groupCode));
        Clients.Group(ShopGroupKey(hotelId, groupCode)).UpdateRoomStatus("UpdateRoomStatus", "UpdateRoomStatus");
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="userLoginName"></param>
    /// <param name="hotelId"></param>
    /// <param name="groupCode"></param>
    [HubMethodName("QuitGroup")]
    public async Task QuitGroupAsync(string userLoginName, string hotelId, string groupCode)
    {
        await Groups.Remove(Context.ConnectionId, ShopGroupKey(hotelId, groupCode));
    }
}

and Client Code:

internal IHubProxy PublicHub;

    internal IHubProxy RoomHub;

    public static SignalRUtility Instance
    {
        get
        {
            if (_instance == null)
            {
                Host = ConfigurationManager.AppSettings["signalRHost"];
                _instance = new SignalRUtility();
            }
            return _instance;
        }
    }

    private SignalRUtility()
    {
        Connection = new HubConnection(Host + "/signalr", useDefaultUrl: false);
        PublicHub = Connection.CreateHubProxy("PublicHub");
        RoomHub = Connection.CreateHubProxy("RoomStatusHub");
        RoomHub.On<string>("UpdateRoomStatus", (code) =>
        {
            if(RoomStatusDelegates != null)
            {
                RoomStatusDelegates(code);
            }
        });

        RoomHub.On<string>("UpdateOrderStatus", (code) =>
        {
            if (OrderStatusDelegates != null)
            {
                OrderStatusDelegates(code);
            }
        });
        Connection.Start().Wait();
    }

Doesn't receive any message from the server side in client side. Client.All can send message.