I have below ItemAccessHub implementation to lock rows that are being edited by users to avoid multiple edits on a same row.

public class ItemAccessHub : Hub
{
    private static readonly ConcurrentDictionary<string, (string ConnectionId, string Module, string Username)> RowLocks = new();

    public override Task OnConnectedAsync()
    {
        return base.OnConnectedAsync();
    }

    public override Task OnDisconnectedAsync(Exception exception)
    {
        var rowId = Context.GetHttpContext().Request.Query["row-id"].ToString();
        if (RowLocks.TryRemove(rowId, out var value) && value.ConnectionId == Context.ConnectionId)
        {
            Clients.Others.SendAsync("RowUnlocked", rowId);
        }

        return base.OnDisconnectedAsync(exception);
    }

    public Task LockRow(string rowId, string module, string username)
    {
        RowLocks[rowId] = (Context.ConnectionId, module, username);
        return Clients.Others.SendAsync("RowLocked", rowId, username);
    }

    public Task UnlockRow(string rowId)
    {
        if (RowLocks.TryRemove(rowId, out var value) && value.ConnectionId == Context.ConnectionId)
        {
            return Clients.Others.SendAsync("RowUnlocked", rowId);
        }
        return Task.CompletedTask;
    }
}

Below is the code on a page where hubconnection gets set:

hubConnection = new HubConnectionBuilder()
   .WithUrl(UriHelper.ToAbsoluteUri("/itemaccesshub"))
    .Build();

hubConnection.On<string, string>("RowLocked", (rowId, username) =>
{
    rowLocks[rowId] = username;
    InvokeAsync(StateHasChanged);
});

hubConnection.On<string>("RowUnlocked", rowId =>
{
    rowLocks.Remove(rowId);
    InvokeAsync(StateHasChanged);
});

await hubConnection.StartAsync();

Now everything else works a part from browser closure or page refresh, means row stays lock forever in these 2 instances.

I want to implement row lock in a way that if 1 user is editing it is locked for other user. If locked user closes or refresh browser the locked row should get released.