Real-time communication has changed how users interact with apps. It powers features like live notifications, instant messaging, gaming, and collaboration tools. One technology that makes this possible is WebSocket. When combined with .NET, WebSocket becomes a powerful tool for building real-time features in apps efficiently and effectively.
This guide will explain what WebSocket is, its benefits, use cases, and how to implement it in .NET. We will also compare it with HTTP, share advanced WebSocket features in .NET Core, and give tips for best practices.

 

 

WebSocket is a communication protocol that allows two-way (full-duplex) communication between a client (like a browser) and a server.

• Unlike HTTP, which works on a request-response model, WebSocket creates a persistent connection.

• Once the connection is established, both the client and server can send messages to each other at any time, without waiting for a request.

• Real-time data streaming: For live dashboards, stock tickers, or real-time notifications.

• Interactive apps: Chat apps, collaborative tools, or online games.

• High-frequency data updates: Apps requiring constant data flow, like IoT systems.

WebSocket offers unique benefits for .NET developers:

 

.NET Core makes working with WebSocket even easier by offering advanced features like:

 

app.UseWebSockets();  
app.Use(async (context, next) => {  
    if (context.Request.Path == "/ws") {  
        if (context.WebSockets.IsWebSocketRequest) {  
            var webSocket = await context.WebSockets.AcceptWebSocketAsync();  
            await HandleWebSocketCommunication(webSocket);  
        }  
    } else {  
        await next();  
    }  
});  

WebSocket allows continuous data streaming, perfect for live feeds like video streams or stock prices.

 

Secure your WebSocket connections with token-based or cookie-based authentication to ensure only authorized users can access the service.

 

SignalR builds on WebSocket to add features like:

 

• Automatic reconnection.

• Broadcasting messages to multiple users.

• Pub/sub architecture for large-scale apps.

 

How to Implement WebSocket in .NET

Step 1: Set Up WebSocket Middleware

Enable WebSocket in your ASP.NET Core app.

app.UseWebSockets();  

 

Step 2: Create WebSocket Handlers

Write a handler to manage WebSocket connections and process incoming/outgoing messages.

private async Task HandleWebSocketCommunication(WebSocket webSocket) {  
    var buffer = new byte[1024 * 4];  
    WebSocketReceiveResult result;  
    do {  
        result = await webSocket.ReceiveAsync(new ArraySegment<byte>(buffer), CancellationToken.None);  
        var message = Encoding.UTF8.GetString(buffer, 0, result.Count);  
        await webSocket.SendAsync(new ArraySegment<byte>(Encoding.UTF8.GetBytes($"Echo: {message}")), WebSocketMessageType.Text, true, CancellationToken.None);  
    } while (!result.CloseStatus.HasValue);  
    await webSocket.CloseAsync(result.CloseStatus.Value, result.CloseStatusDescription, CancellationToken.None);  
}  

 

Step 3: Connect with a WebSocket Client

Use JavaScript on the client side to establish a WebSocket connection.

const socket = new WebSocket("ws://localhost:5000/ws");  
socket.onopen = () => {  
    console.log("Connected");  
    socket.send("Hello Server!");  
};  
socket.onmessage = (event) => {  
    console.log("Message from server: ", event.data);  
};  

 

Best Practices for WebSocket in .NET

1. Error Handling

2. Data Security

3. Load Balancing

4. Testing

5. Scalability

Use SignalR for large apps that need features like reconnection and message broadcasting.

 

Benefits of WebSocket in .NET Applications

Conclusion