Send a message to only one user with signalR

Question

I am writing a chat application. I use Angular 6 and .Net Core 3.1.

I have read a lot of documents but still do not understand where there is an error.

My Hub Class

public class ChatHub : Hub
{ 
    private static List<ConnectedUser> _connectedUsers = new List<ConnectedUser>();

    public override Task OnConnectedAsync()
    {
        var username = Context.GetHttpContext().Request.Query["username"];

        var status = _connectedUsers.FirstOrDefault(x => x.Username == username);

        if (status == null)
        {
            _connectedUsers.Add(new ConnectedUser
            {
                ConnId = Context.ConnectionId,
                Username = username
            });

        }

        return base.OnConnectedAsync();
    } 
    ...

I have a list that keeps the connection id information of the users connected in my Hub Class. When users connect, I add to this list.

I operate in my Private Chat Function below.

public void PrivateChat(string toUser,string fromUser,string message)
{
    _connectedUsers.ForEach(val =>
    {
        if(val.Username == toUser)
           Clients.User(val.ConnId).SendAsync("receiveMessage", message,fromUser);
    });
}

However, I cannot return to the user I want.

You use it in Angular this way

this._hubConnection.on('receiveMessage', (message,fromUser) => {
     console.log(message , "+" , fromUser);
  }
);

Answer 1

You should use

 Clients.Clients(val.ConnId).SendAsync("receiveMessage", message,fromUser);