向窗体的系统菜单添加菜单项

 [System.Runtime.InteropServices.DllImport("user32")]
  private static extern IntPtr GetSystemMenu(IntPtr hwnd,bool bRevert);
 
  [System.Runtime.InteropServices.DllImport("user32")]
  private static extern IntPtr AppendMenu(IntPtr hMenu,int wFlags,IntPtr wIDNewItem,string lpNewItem);
  
  const int MF_POPUP = 0x0010;
  const int MF_SEPARATOR = 0x0800;
 
 
将 mainMenu1 菜单添加到系统菜单
 
  private void Form1_Load(object sender, System.EventArgs e)
  {
       IntPtr mnuSystem;
       mnuSystem=GetSystemMenu(this.Handle,false);
       AppendMenu(mnuSystem, MF_SEPARATOR, (IntPtr)0, "");

       for(int i= 0;i<this.mainMenu1.MenuItems.Count;i++)
       {
            AppendMenu(mnuSystem,MF_POPUP,this.mainMenu1.MenuItems[i].Handle,this.mainMenu1.MenuItems[i].Text);
       }
  }