using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace ProcessTest
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();

worker.WorkerReportsProgress = true;

worker.WorkerSupportsCancellation = true;

//正式做事情的地方
            worker.DoWork+=new DoWorkEventHandler(DoWork);

//任务完称时要做的，比如提示等等
            worker.ProgressChanged += new ProgressChangedEventHandler(ProgessChanged);

//任务进行时，报告进度
            worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(CompleteWork);
        }

//调用 RunWorkerAsync 时发生
        public void DoWork(object sender, DoWorkEventArgs e)
        {
            e.Result = ComputeFibonacci(worker, e);
            //获取异步操作结果的值，当ComputeFibonacci(worker, e)返回时，异步过程结束
        }

//调用 ReportProgress 时发生
        public void ProgessChanged(object sender, ProgressChangedEventArgs e)
        {
            this.progressBar1.Value = e.ProgressPercentage;
            //将异步任务进度的百分比赋给进度条
        }

//当后台操作已完成、被取消或引发异常时发生
        public void CompleteWork(object sender, RunWorkerCompletedEventArgs e)
        {
            MessageBox.Show("完成！");
        }

private int ComputeFibonacci(object sender, DoWorkEventArgs e)
        {
            for (int i = 0; i < 1000; i++)
            {
                //判断应用程序是否取消后台操作
                if(worker.CancellationPending)
                {
                    e.Cancel = true;
                }
                else
                {
                    worker.ReportProgress(i);
                }

System.Threading.Thread.Sleep(10);
            }
            return -1;
        }

private void btnStart_Click(object sender, EventArgs e)
        {
            worker.RunWorkerAsync();

btnStart.Enabled = false;

btnPause.Enabled = true;
        }

private void btnPause_Click(object sender, EventArgs e)
        {
            btnPause.Enabled = false;

btnStart.Enabled = true;

worker.CancelAsync();
        }
    }
}