public class DataWrite
 {
  public delegate void UpdateUI(int step);//聲明一個更新主線程的委托
  public UpdateUI UpdateUIDelegate;

  public delegate void AccomplishTask();//聲明一個在完成任務(wù)時通知主線程的委托
  public AccomplishTask TaskCallBack;
  
  public void Write(object lineCount)
  {
   StreamWriter writeIO = new StreamWriter("text.txt", false, Encoding.GetEncoding("gb2312"));
   string head = "編號,省,市";
   writeIO.Write(head);
   for (int i = 0; i < (int)lineCount; i++)
   {
    writeIO.WriteLine(i.ToString() + ",湖南,衡陽");
    //寫入一條數(shù)據(jù)，調(diào)用更新主線程ui狀態(tài)的委托
    UpdateUIDelegate(1);
   }
   //任務(wù)完成時通知主線程作出相應(yīng)的處理
   TaskCallBack();
   writeIO.Close();
  }
 }

delegate void AsynUpdateUI(int step);

  private void btnWrite_Click(object sender, EventArgs e)
  {
   int taskCount = 10000; //任務(wù)量為10000
   this.pgbWrite.Maximum = taskCount;
   this.pgbWrite.Value = 0;

   DataWrite dataWrite = new DataWrite();//實例化一個寫入數(shù)據(jù)的類
   dataWrite.UpdateUIDelegate += UpdataUIStatus;//綁定更新任務(wù)狀態(tài)的委托
   dataWrite.TaskCallBack += Accomplish;//綁定完成任務(wù)要調(diào)用的委托

   Thread thread = new Thread(new ParameterizedThreadStart(dataWrite.Write));
   thread.IsBackground = true;
   thread.Start(taskCount);
  }

  //更新UI
  private void UpdataUIStatus(int step)
  {
   if (InvokeRequired)
   {
    this.Invoke(new AsynUpdateUI(delegate(int s)
    {
     this.pgbWrite.Value += s;
     this.lblWriteStatus.Text = this.pgbWrite.Value.ToString() + "/" + this.pgbWrite.Maximum.ToString();
    }), step);
   }
   else
   {
    this.pgbWrite.Value += step;
    this.lblWriteStatus.Text = this.pgbWrite.Value.ToString() + "/" + this.pgbWrite.Maximum.ToString();
   }
  }

  //完成任務(wù)時需要調(diào)用
  private void Accomplish()
  {
   //還可以進(jìn)行其他的一些完任務(wù)完成之后的邏輯處理
   MessageBox.Show("任務(wù)完成");
  }