C#实现系统热键的功能

利用windows api方式实现系统热键的功能！
主要类设计如下：
using System;
using System.Windows.Forms; // for Key namespace
using System.Runtime.InteropServices;
 
namespace 实现系统热键
{
 /// <summary>
 /// WIN32 Windows API辅助操作类.
 /// </summary>
 public class NativeWIN32
 {
  public NativeWIN32()
  {}
  /* ------- using WIN32 Windows API in a C# application ------- */
 
  [DllImport("user32.dll", CharSet=CharSet.Auto)]
  static public extern IntPtr GetForegroundWindow(); //
 
  [StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto)]
   public struct STRINGBUFFER
  {
   [MarshalAs(UnmanagedType.ByValTStr, SizeConst=256)]
   public string szText;
  }
 
  [DllImport("user32.dll", CharSet=CharSet.Auto)]
  public static extern int GetWindowText(IntPtr hWnd,  out STRINGBUFFER ClassName, int nMaxCount);
 
  [DllImport("user32.dll", CharSet=CharSet.Auto)]
  public static extern int SendMessage(IntPtr hWnd, int msg, int wParam, int lParam);
 
  [DllImport("user32.dll", CharSet=CharSet.Auto)]
  public static extern IntPtr SendMessage(IntPtr hWnd, int msg, int wParam, IntPtr lParam);
 
  public const int WM_SYSCOMMAND = 0x0112;
  public const int SC_CLOSE = 0xF060;
 
  public delegate bool EnumThreadProc(IntPtr hwnd, IntPtr lParam);
 
  [DllImport("user32.dll", CharSet=CharSet.Auto)]
  public static extern bool EnumThreadWindows(int threadId, EnumThreadProc pfnEnum, IntPtr lParam);
 
  [DllImport("user32.dll", CharSet=CharSet.Auto)]
  public static extern IntPtr FindWindowEx(IntPtr parent, IntPtr next, string sClassName, IntPtr sWindowTitle);
 

  /* ------- using HOTKEYs in a C# application -------
 
  in form load :
   bool success = RegisterHotKey(Handle, 100,     KeyModifiers.Control | KeyModifiers.Shift, Keys.J);
 
  in form closing :
   UnregisterHotKey(Handle, 100);
  
 
  protected override void WndProc( ref Message m )
  {
   const int WM_HOTKEY = 0x0312; 
  
   switch(m.Msg)
   {
    case WM_HOTKEY: 
     MessageBox.Show("Hotkey pressed"); 
     break;
   } 
   base.WndProc(ref m );
  }
 
  ------- using HOTKEYs in a C# application ------- */
 
  [DllImport("user32.dll", SetLastError=true)]
  public static extern bool RegisterHotKey( IntPtr hWnd, // handle to window   
   int id,            // hot key identifier   
   KeyModifiers fsModifiers,  // key-modifier options   
   Keys vk            // virtual-key code   
   );
 
  [DllImport("user32.dll", SetLastError=true)]
  public static extern bool UnregisterHotKey( IntPtr hWnd,  // handle to window   
   int id      // hot key identifier   
   );
 
  [Flags()]
   public enum KeyModifiers
  { 
   None = 0,
   Alt = 1,   
   Control = 2,   
   Shift = 4,   
   Windows = 8
  }
 }
}