How is C++ used with websockets?

The steps to using WebSocket in C++ are as follows:

1. Introducing WebSocket library: The first step is to bring in a WebSocket library, such as Boost.Asio, cpprestsdk, etc. These libraries provide the necessary functions for WebSocket.
2. Creating a WebSocket object: Use the API provided by the WebSocket library to create a WebSocket object. For example, with the cpprestsdk library, you can use the websocketpp::client class to create a WebSocket client object.
3. Connect to the WebSocket server: Use the connect method of the WebSocket object to establish a connection with the WebSocket server. You need to specify the address and port number of the server.
4. Sending and receiving messages: You can use the send method of the WebSocket object to send messages to the server. At the same time, you can also receive messages sent by the server by setting a callback function.
5. Close WebSocket connection: Use the close method of the WebSocket object to terminate the WebSocket connection.

Here is an example code using the cpprestsdk library to create a WebSocket client.

#include <cpprest/ws_client.h> 

int main()
{
    web::websockets::client::websocket_callback_client client;

    // 连接到WebSocket服务器
    client.connect("ws://localhost:8080").then([]() {
        std::cout << "Connected to server" << std::endl;
    });

    // 发送消息
    client.send("Hello, server!");

    // 接收消息回调函数
    client.set_message_handler([](web::websockets::client::websocket_incoming_message msg) {
        std::cout << "Received message: " << msg.extract_string().get() << std::endl;
    });

    // 关闭连接
    client.close().then([]() {
        std::cout << "Disconnected from server" << std::endl;
    });

    return 0;
}

This is a simple WebSocket client example that connects to the ws://localhost:8080 server, sending and receiving messages. You can modify the code according to your own needs to adapt to different situations.