I'm using ASP.net signalR. Windows application .Net

Question

After the client's network disconnects, the SignalR connection persists, but the client does not receive notifications. We make a request to the server, and the server responds, but the client still does not receive notifications even when a new request is created from the client after the network comes back up.
I'm using ASP.net signalR. Windows application .Net

Answer 1

In ASP.NET SignalR, if the client does not receive notifications after the network disconnects and reconnects, it may be due to the client not properly handling the reconnection process. When the network is restored, the SignalR client should attempt to reconnect automatically. If it does not, you may need to implement custom logic to handle reconnections and ensure that the client is notified of any messages or events after the connection is re-established.

You can listen for the Closed event on the HubConnection to handle cases when the connection is lost. Additionally, you can configure automatic reconnect attempts using the WithAutomaticReconnect method to specify how the client should behave when the connection is interrupted. Here’s a basic example:

connection.Closed += error =>
{
    // Logic to handle connection closure
    // Attempt to reconnect or notify the user
};

HubConnection connection = new HubConnectionBuilder()
    .WithUrl(new Uri("http://yourserver/chathub"))
    .WithAutomaticReconnect()
    .Build();

Make sure that your server is also set up to handle reconnections properly and that the client is subscribed to the necessary events to receive notifications after reconnecting. If the client is not receiving notifications after a new request is made, ensure that the hub methods are declared as public and that the client is correctly invoking these methods after the connection is restored.

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References:

• ASP.NET Core SignalR .NET Client
• SignalR Troubleshooting

Answer 2

Hello Pavithra,

Thanks for the extra details. When SignalR stops delivering messages after the network comes back, the usual cause is that the client reconnects but doesn’t fully restore its state.

A few things worth checking on your side:

• Make sure the client re-runs whatever setup your app needs after reconnect (joining groups, calling your init method, or reattaching handlers). This is a known behavior, handlers or subscriptions may not survive a reconnect: https://stackoverflow.com/questions/41593728/signalr-client-does-not-receive-messages-after-a-reconnection
• Confirm that the connection actually reaches a proper “Reconnected” state. SignalR reconnect isn’t automatic unless you explicitly enable it: https://learn.microsoft.com/en-us/aspnet/core/signalr/dotnet-client?view=aspnetcore-9.0#reconnect-clients
• After reconnect, the connection ID usually changes. If your server is still sending to the old ID, the client won’t get anything. This is documented and commonly reported: https://github.com/dotnet/aspnetcore/discussions/54818
• If you’re testing in a specific environment (VPN, proxy, corporate network), those can interrupt long-running WebSocket connections. So it’s worth verifying the behavior on the machine/environment where your app normally runs.

(Disclaimer: Some links are non-Microsoft website. The pages appear to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classifies as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the site before you decide to download and install it.) 
Hope this helps!