C#结合使用WebClient和计时器来主动显示更新的数据

using System;
using System.Net;
using System.Threading.Tasks;
using System.Windows.Forms;

public class UpdateForm : Form
{
    private Label updateLabel;
    private Timer timer;

    public UpdateForm()
    {
        updateLabel = new Label { Text = "等待更新...", AutoSize = true };
        this.Controls.Add(updateLabel);

        timer = new Timer();
        timer.Interval = 5000; // 每5秒更新一次
        timer.Tick += Timer_Tick;
        timer.Start();
    }

    private async void Timer_Tick(object sender, EventArgs e)
    {
        try
        {
            string data = await FetchDataAsync("https://api.example.com/data");
            updateLabel.Text = $"更新时间: {DateTime.Now} - 数据: {data}";
        }
        catch (Exception ex)
        {
            updateLabel.Text = $"更新失败: {ex.Message}";
        }
    }

    private async Task<string> FetchDataAsync(string url)
    {
        using (WebClient client = new WebClient())
        {
            return await client.DownloadStringTaskAsync(url);
        }
    }

    [STAThread]
    static void Main()
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new UpdateForm());
    }
}