C#:在漫长的过程中显示模态进度对话框

using System;
using System.ComponentModel;
using System.Threading;
using System.Windows.Forms;

public class ProgressForm : Form
{
    private BackgroundWorker worker;
    private ProgressBar progressBar;

    public ProgressForm()
    {
        InitializeComponent();
        worker = new BackgroundWorker();
        worker.WorkerReportsProgress = true;
        worker.DoWork += Worker_DoWork;
        worker.ProgressChanged += Worker_ProgressChanged;
        worker.RunWorkerCompleted += Worker_RunWorkerCompleted;
    }

    private void InitializeComponent()
    {
        progressBar = new ProgressBar();
        Controls.Add(progressBar);
    }

    private void Worker_DoWork(object sender, DoWorkEventArgs e)
    {
        // 在这里执行耗时的操作
        for (int i = 0; i <= 100; i++)
        {
            // 模拟进度更新
            Thread.Sleep(100);
            worker.ReportProgress(i);
        }
    }

    private void Worker_ProgressChanged(object sender, ProgressChangedEventArgs e)
    {
        // 更新进度条的值
        progressBar.Value = e.ProgressPercentage;
    }

    private void Worker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        // 操作完成后的处理
        MessageBox.Show("操作已完成！");
        Close();
    }

    public void Start()
    {
        // 启动后台操作
        worker.RunWorkerAsync();
        ShowDialog();
    }
}

// 在你的代码中调用ProgressForm来显示模态进度对话框
public class YourClass
{
    public void YourMethod()
    {
        ProgressForm progressForm = new ProgressForm();
        progressForm.Start();
    }
}