how to override SignalR methods in mvc 5 - model-view-controller

Question

I am working on a asp.net mvc5 project and I want to implement chatroom with signalR So I got Microsoft.Aspnet.SignalR from nuget and I used a SignalR Hub class for hub and now i want to override OnDisconnected() method .but I get error
'ChatHub.OnDisconnected()': no suitable method found to override
I dont know how to solve this problem please help me
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using Microsoft.AspNet.SignalR;
using System.Collections.Concurrent;
using System.Threading.Tasks;
namespace WebApplication3.Hubs
{
public class ChatHub : Hub
{
public void Hello()
{
Clients.All.hello();
}
static ConcurrentDictionary<string, string> dic = new ConcurrentDictionary<string, string>();
public void Send(string name, string message)
{
Clients.All.broadcastMessage(name, message);
}
public void SendToSpecific(string name, string message, string to)
{
// Call the broadcastMessage method to update clients.
Clients.Caller.broadcastMessage(name, message);
Clients.Client(dic[to]).broadcastMessage(name, message);
}
public void Notify(string name, string id)
{
if (dic.ContainsKey(name))
{
Clients.Caller.differentName();
}
else
{
dic.TryAdd(name, id);
foreach (KeyValuePair<String, String> entry in dic)
{
Clients.Caller.online(entry.Key);
}
Clients.Others.enters(name);
}
}
public override Task OnDisconnected()
{
var name = dic.FirstOrDefault(x => x.Value == Context.ConnectionId.ToString());
string s;
dic.TryRemove(name.Key, out s);
return Clients.All.disconnected(name.Key);
}
}
}

Answer 1

For SignalR 2.1.0+, you need to use OnDisconected(bool stopCalled).
// Microsoft.AspNet.SignalR.Hub
// Summary:
// Called when a connection disconnects from this hub gracefully or due to a timeout.
//
// Parameters:
// stopCalled:
// true, if stop was called on the client closing the connection gracefully; false,
// if the connection has been lost for longer than the Microsoft.AspNet.SignalR.Configuration.IConfigurationManager.DisconnectTimeout.
// Timeouts can be caused by clients reconnecting to another SignalR server in scaleout.
//
// Returns:
// A System.Threading.Tasks.Task
public virtual Task OnDisconnected(bool stopCalled);