C# 委托的一个例子

/// <summary>
  /// 任务委托
  /// </summary>
  delegate void TaskDelegate();


/// <summary>
  /// 任务
  /// </summary>
  public void Task()
  {

  }

// 开始异步Task
   TaskDelegate task = new TaskDelegate(Task);
   task.BeginInvoke(null, null);





/// <summary>
  /// 更新界面委托
  /// </summary>
  private delegate void ProgressEventsHandler( object sender, ProgressEventArgs e);

/// <summary>
  /// 更新界面
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  private void UpdateUI(object sender, ProgressEventArgs e)
  {
      //改变进度条位置
      progressBar1.Value += e.PercentIncrease1;     
  }

object[] pList = { this, e };
 BeginInvoke(new ProgressEventsHandler(UpdateUI), pList);