using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace 异步委托和线程调用
{
 /// <summary>
 /// Form1 的摘要说明。
 /// </summary>
 public class Form1 : System.Windows.Forms.Form
 {
#region 默认代码
  private System.Windows.Forms.Button button1;
  private System.Windows.Forms.Button button2;
  private System.Windows.Forms.ProgressBar progressBar1;
  /// <summary>
  /// 必需的设计器变量。
  /// </summary>
  private System.ComponentModel.Container components = null;

  public Form1()
  {
   //
   // Windows 窗体设计器支持所必需的
   //
   InitializeComponent();

   //
   // TODO: 在 InitializeComponent 调用后添加任何构造函数代码
   //
  }

  /// <summary>
  /// 清理所有正在使用的资源。
  /// </summary>
  protected override void Dispose( bool disposing )
  {
   if( disposing )
   {
    if (components != null)
    {
     components.Dispose();
    }
   }
   base.Dispose( disposing );
  }

  #region Windows 窗体设计器生成的代码
  /// <summary>
  /// 设计器支持所需的方法 - 不要使用代码编辑器修改
  /// 此方法的内容。
  /// </summary>
  private void InitializeComponent()
  {
   this.button1 = new System.Windows.Forms.Button();
   this.button2 = new System.Windows.Forms.Button();
   this.progressBar1 = new System.Windows.Forms.ProgressBar();
   this.SuspendLayout();
   //
   // button1
   //
   this.button1.Location = new System.Drawing.Point(147, 12);
   this.button1.Name = "button1";
   this.button1.Size = new System.Drawing.Size(116, 28);
   this.button1.TabIndex = 0;
   this.button1.Text = "使用线程=>";
   this.button1.Click += new System.EventHandler(this.button1_Click);
   //
   // button2
   //
   this.button2.Location = new System.Drawing.Point(147, 44);
   this.button2.Name = "button2";
   this.button2.Size = new System.Drawing.Size(116, 28);
   this.button2.TabIndex = 0;
   this.button2.Text = "使用异步委托=>";
   this.button2.Click += new System.EventHandler(this.button2_Click);
   //
   // progressBar1
   //
   this.progressBar1.Location = new System.Drawing.Point(0, 80);
   this.progressBar1.Maximum = 1000;
   this.progressBar1.Name = "progressBar1";
   this.progressBar1.Size = new System.Drawing.Size(412, 12);
   this.progressBar1.TabIndex = 1;
   //
   // Form1
   //
   this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
   this.ClientSize = new System.Drawing.Size(410, 94);
   this.Controls.Add(this.progressBar1);
   this.Controls.Add(this.button1);
   this.Controls.Add(this.button2);
   this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedToolWindow;
   this.Name = "Form1";
   this.Text = "Form1";
   this.Closed += new System.EventHandler(this.Form1_Closed);
   this.ResumeLayout(false);

  }
  #endregion

  /// <summary>
  /// 应用程序的主入口点。
  /// </summary>
  [STAThread]
  static void Main()
  {
   Application.Run(new Form1());
  }
#endregion
  
  //线程
  private void button1_Click(object sender, System.EventArgs e)
  {
   System.Threading.Thread th = new System.Threading.Thread(
    new System.Threading.ThreadStart(Fun2));   
   this.processEvent += new myProcessEventHandle(Form1_processEvent);
   th.Start();
   button2.Enabled = false;
  }

  //异步委托
  private void button2_Click(object sender, System.EventArgs e)
  {
   System.Threading.WaitCallback wc = new System.Threading.WaitCallback(Fun);
   object obj = this.button1;//这里没用。到时候你可以用来传递参数
   this.processEvent += new myProcessEventHandle(Form1_processEvent);
   System.Threading.ThreadPool.QueueUserWorkItem(wc,obj);   
   button1.Enabled = false;
  }

  public delegate void myProcessEventHandle(int percent);//定义事件
  public event myProcessEventHandle processEvent = null;//事件声明

  //线程无法带参数启动，和这个函数通讯直接用成员变量就可以了
  private void Fun2()
  {
   int i = 0;
   String str = this.Text;
   while (i<1000)
   {
    i++;
    //this.Text = i.ToString();
    if (this.processEvent != null)
    {
     this.processEvent(i);
    }
    System.Threading.Thread.Sleep(8);
   }   
   TelMe();
   this.Text = str;
  }

  //异步委托可以也必须要一个参数，当然不想用就传一个null就可以了
  private void Fun(object obj)
  {
   int i = 0;
   String str = this.Text;
   while (i<1000)
   {
    i++;
    //this.Text = i.ToString();
    if (this.processEvent != null)
    {
     this.processEvent(i);
    }
    System.Threading.Thread.Sleep(8);
   }   
   TelMe();
   this.Text = str;
  }

  //不是回调，但是同一个类里写的，就可以直接调用了。
  private void TelMe()
  {
   this.processEvent -= new myProcessEventHandle(Form1_processEvent);
   button1.Enabled = true;
   button2.Enabled = true;
   MessageBox.Show("操作完成！");
  }

  //事件方式通知主线程进度
  private void Form1_processEvent(int percent)
  {
   this.progressBar1.Value = percent;
   this.Text = ((double)percent/10).ToString() + "%";
  }

  private void Form1_Closed(object sender, System.EventArgs e)
  {
   System.Environment.Exit(0);//用于退出没有运行结束的线程
  }
 }
}

//以上代码在vs2003可以运行。以前写的例子。

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