SignalR Client How to Set user when start connection?

try this with queryString in asp.netcore 2.1:

Client (javascript) set query string after url like follow:

var connection = new signalR.HubConnectionBuilder().withUrl("http://localhost:10499/chathub?username=xxxx").build();
connection.start().then(function ()
{
    // do some thing here ...
}).catch(function (err)
{
    console.error(err.toString());
});
.
.
.

Server

public override Task OnConnectedAsync()
    {
        var  username = Context.GetHttpContext().Request.Query["username"];
        // username = xxxx
        return base.OnConnectedAsync();
    }

Pass your username using query string.

Client

First set query string

string url = @"http://localhost:8080/";
var connection = new HubConnection(url);
_hub = connection.CreateHubProxy("TestHub");
connection.qs = { 'username' : 'anik' };
connection.Start().Wait();

Server

public override Task OnConnected()
{
    var username= Context.QueryString['username'];
    return base.OnConnected();
}