Establishing Connections with SignalR

Syntax

const connection = new signalR.HubConnectionBuilder()
    .withUrl("http://localhost:5000/chatHub")
    .build();

Example

const connection = new signalR.HubConnectionBuilder()
    .withUrl("http://localhost:5000/chatHub")
    .build();

// Start the connection.
connection.start().then(() => {
   console.log("Connected successfully."); 
}).catch((err) => {
    console.log("Error connecting to server: " + err);
});

Output

If the connection is established successfully, the console will log "Connected successfully." Otherwise, it will log an error message with the reason why the connection failed.

Explanation

SignalR is a real-time communication library for ASP.NET Core applications. In order to use SignalR, you need to establish a connection between the client and the server. The HubConnectionBuilder is used to create a connection object that can be used to communicate with the SignalR server.

In the example above, we are creating a connection with a SignalR hub located at http://localhost:5000/chatHub. The start() method is used to initiate the connection. If the connection is successful, a Connected event is triggered.

Use

Establishing connections with SignalR is essential for real-time communication between the client and server. You can use SignalR to build real-time chat applications, multiplayer games, and more.

Important Points

• The HubConnectionBuilder is used to create a connection object that can be used to communicate with a SignalR server.
• The withUrl() method is used to specify the URL of the SignalR hub.
• The start() method is used to initiate the connection between the client and server.
• If the connection is successful, a Connected event is triggered.

Summary

In this article, we discussed how to establish connections with SignalR using the HubConnectionBuilder. We provided a syntax example, demonstrated the output of establishing a successful or unsuccessful connection, explained the use case/application use, and provided important points to remember when working with SignalR.