SignalR Tutorial: How to Implement SignalR in .NET Core Web App

Learn how SignalR in .NET Core simplifies real-time app development with instant client-server communication.

What is SignalR?

SignalR is a Microsoft library for adding real-time functionality to web apps, enabling server push updates automatically to clients.

Key Features of SignalR

• Real-time bidirectional communication between server and clients.
• Automatic protocol selection: WebSockets, SSE, Long Polling.
• Scalability via Azure SignalR Service.
• Group management for broadcasting messages.
• Supports multiple languages (JavaScript, .NET, Java).
• Built-in authentication, encryption, and digital signatures.
• Extensible and customizable architecture.

Steps to Implement SignalR in .NET Core

1. Install SignalR NuGet Package

dotnet add package Microsoft.AspNetCore.SignalR

2. Add SignalR Middleware

builder.Services.AddSignalR();
app.MapHub("/chatHub");

3. Create a Hub

public class ChatHub : Hub
{
    public async Task SendMessage(string user, string message)
    {
        await Clients.All.SendAsync("ReceiveMessage", user, message);
    }
}

4. Add Client-Side Scripts

Include SignalR’s JavaScript library via CDN or locally.

5. Create a View

Set up a simple chat interface in your Razor view for testing real-time messages.

6. Run Your Application

Test the SignalR real-time functionality by starting your app and interacting with the chat interface.

Github Repository

Clone the demo app: signalr-example

Conclusion

SignalR in .NET Core enables real-time, scalable web applications. Follow this guide to implement SignalR in your projects efficiently.