js 实时获取数据

function fetchData() {
    fetch('https://api.example.com/data')
        .then(response => response.json())
        .then(data => {
            console.log('Data:', data);
            // 更新UI
            setTimeout(fetchData, 5000); // 每5秒轮询一次
        })
        .catch(error => console.error('Error:', error));
}

fetchData();

const socket = new WebSocket('wss://api.example.com/socket');

socket.addEventListener('open', function (event) {
    console.log('WebSocket connection opened');
    socket.send('Hello Server!');
});

socket.addEventListener('message', function (event) {
    console.log('Message from server:', event.data);
    // 更新UI
});

socket.addEventListener('close', function (event) {
    console.log('WebSocket connection closed');
});

socket.addEventListener('error', function (event) {
    console.error('WebSocket error:', event);
});

const eventSource = new EventSource('https://api.example.com/events');

eventSource.addEventListener('message', function (event) {
    console.log('Message from server:', event.data);
    // 更新UI
});

eventSource.addEventListener('error', function (event) {
    console.error('EventSource error:', event);
});