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

namespace Example106_監視剪貼板
{
	/// <summary>
	/// Form1 的摘要說明。
	/// </summary>
	public class Form1 : System.Windows.Forms.Form
	{
		/// <summary>
		/// 必需的設計器變量。
		/// </summary>
		private System.ComponentModel.Container components = null;

		public Form1()
		{
			//
			// Windows 窗體設計器支持所必需的
			//
			InitializeComponent();

			//
			// TODO: 在 InitializeComponent 調用后添加任何構造函數代碼
			//
		}

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

		#region Windows Form Designer generated code
		/// <summary>
		/// 設計器支持所需的方法 - 不要使用代碼編輯器修改
		/// 此方法的內容。
		/// </summary>
		private void InitializeComponent()
		{
			this.richTextBox1 = new System.Windows.Forms.RichTextBox();
			this.SuspendLayout();
			// 
			// richTextBox1
			// 
			this.richTextBox1.Location = new System.Drawing.Point(8, 8);
			this.richTextBox1.Name = "richTextBox1";
			this.richTextBox1.Size = new System.Drawing.Size(216, 152);
			this.richTextBox1.TabIndex = 0;
			this.richTextBox1.Text = "richTextBox1";
			// 
			// Form1
			// 
			this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
			this.ClientSize = new System.Drawing.Size(232, 165);
			this.Controls.AddRange(new System.Windows.Forms.Control[] {
																		  this.richTextBox1});
			this.Name = "Form1";
			this.Text = "Form1";
			this.Load += new System.EventHandler(this.Form1_Load);
			this.Closed += new System.EventHandler(this.Form1_Closed);
			this.ResumeLayout(false);

		}
		#endregion

		/// <summary>
		/// 應用程序的主入口點。
		/// </summary>
		[STAThread]
		static void Main() 
		{
			Application.Run(new Form1());
		}

		private System.Windows.Forms.RichTextBox richTextBox1;

		[System.Runtime.InteropServices.DllImport("user32")]
		private static extern IntPtr SetClipboardViewer(IntPtr hwnd);
		[System.Runtime.InteropServices.DllImport("user32")]
		private static extern IntPtr ChangeClipboardChain(IntPtr hwnd,IntPtr hWndNext);
		[System.Runtime.InteropServices.DllImport("user32")]
		private static extern int SendMessage(IntPtr hwnd,int wMsg,IntPtr wParam,IntPtr lParam);

		const int WM_DRAWCLIPBOARD = 0x308;
		const int WM_CHANGECBCHAIN = 0x30D;
		IntPtr NextClipHwnd;
		//觀察鏈中下一個窗口句柄	

		private void Form1_Load(object sender, System.EventArgs e)
		{
			NextClipHwnd=SetClipboardViewer(this.Handle);
			//獲得觀察鏈中下一個窗口句柄		
			DateTime.Now
		}

		private void Form1_Closed(object sender, System.EventArgs e)
		{
			ChangeClipboardChain(this.Handle,NextClipHwnd);
			//從觀察鏈中刪除本觀察窗口
			SendMessage(NextClipHwnd,WM_CHANGECBCHAIN,this.Handle,NextClipHwnd);
			//將WM_DRAWCLIPBOARD消息傳遞到下一個觀察鏈中的窗口		
		}

		protected override void WndProc(ref System.Windows.Forms.Message m)
		{
			switch(m.Msg)
			{
				case WM_DRAWCLIPBOARD:
					SendMessage(NextClipHwnd,m.Msg,m.WParam,m.LParam);
					//將WM_DRAWCLIPBOARD消息傳遞到下一個觀察鏈中的窗口
					IDataObject iData = Clipboard.GetDataObject();
					if(iData.GetDataPresent(DataFormats.Text)|iData.GetDataPresent(DataFormats.OemText)) 
					{
						this.richTextBox1.Text=(String)iData.GetData(DataFormats.Text); 
						
					}
					break;
				default:
					base.WndProc(ref m);
					break;
			}		
		}
	}
}