// Server url : http://localhost/myconnection.ashx
public class MyConnection : PersistentConnection {
    protected override void OnReceived(string clientId, string data) {
        // Broadcast data to all clients
        Connection.Broadcast(data);
    }
}

<script type="text/javascript">
$(function () {
    var connection = $.connection('myconnection.ashx');

    connection.received(function (data) {
        $('<li/>').html(data).appendTo($('#messages'));
    });
    
    connection.start();
    
    $("#broadcast").click(function () {
        connection.send($('#msg').val());
    });
});
</script>

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

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

var connection = new Connection("http://localhost/myconnection.ashx");
connection.Received += data => {
    Console.WriteLine(data);
};

connection.Start().Wait();
connection.Send("From C#");

var connection = new Connection("http://localhost/myconnection.ashx");
connection.AsObservable()
          .Subscribe(Console.WriteLine);

connection.Start().Wait();
connection.Send("From C#");

public class Chat : Hub {
    public void Send(string message) {
        // Call the addMessage method on all clients
        Clients.addMessage(message);
    }
}

<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.addMessage = function(message) {
        $('<li/>').html(data).appendTo($('#messages'));
    };
    
    $("#broadcast").click(function () {
        // Call the chat method on the server
        chat.send($('#msg').val())
            .fail(function(e) { alert(e); }) // Supports jQuery deferred
    });
    
    // Start the connection
    $.connection.hub.start();
});
</script>

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

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