Adding a connection to a group

Multiple clients can connect to a specific Hub at the same time, and the number of connections can easily increase. SignalR offers a feature called groups in order to define subsets of connections and use them when broadcasting to clients. We will see how a Hub can place connected clients into groups and then broadcast calls to all the connections belonging to a specific group.

Getting ready

Before writing the actual code, we need to create a new empty web application, which we'll call Recipe08.

How to do it…

We're ready to start building our sample. We need to perform the following steps:

1. Add a Hub called EchoHub.

2. Add an OWIN Startup class named Startup with a Configuration() method calling app.MapSignalR();.

3. Add the following to the Hub code:

   using Microsoft.AspNet.SignalR;
   using Microsoft.AspNet.SignalR.Hubs;
   
   namespace Recipe08
   {
       [HubName("echo")]
       public class EchoHub : Hub
       {
           public void Subscribe(string groupName)
           {
               Groups...