一个虚拟桌面程序的实现

        前几天为朋友写了一个小工具，主要是为了做到一键隐藏大智慧炒股软件，第一个版本是利用窗口查找，然后向窗口发送WM_SHOW消息完成的。实现原理虽然简单，但是不具备通用性，按我最初的设想要一键隐藏什么软件应该由用户定义，而不是每次都要定制。于是这个小工具的第二个版本诞生了，那就是为用户虚拟一个桌面，然后在虚拟桌面启动explorer进程，用户可以用"ALT+Q"来切换现有桌面与这个虚拟桌面，用户需要运行什么软件，自己在虚拟桌面打开就是了。原理很简单，实现同样也很简单，下面是代码：

/*******************************************************************************



Module:		SunBear.cpp



Date:		2008/06/13



Notice:		Copyright (C)	2008	常海龙



*******************************************************************************/



#include<afxwin.h>



HINSTANCE hInst;				//当前实例

TCHAR szAppName[] = TEXT ("VirtualDesk") ;		//程序名称

HWND  hwnd ;				//主窗体句柄

HDESK hVirtualDesk;				//虚拟桌面句柄

HDESK hCurrent;				//当前桌面句柄



PROCESS_INFORMATION piExplor;			//Explorer进程的PROCESS_INFORMATION结构



LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM);



//每次运行首先检测注册表相关項，如果未发现，则设置开机自动运行

void SetStartup(HINSTANCE hInst)

{

	HKEY hKey;



	DWORD DataType = REG_SZ;



	PCSTR data_run = "Software//Microsoft//Windows//CurrentVersion//Run";

	

	long ret = RegOpenKeyEx(HKEY_LOCAL_MACHINE,data_run,0,KEY_ALL_ACCESS,&hKey);

	

	if(ret != ERROR_SUCCESS)

	{

		MessageBox(NULL,"无法打开注册表键","Error",0);

		return;

	}

	

	CString ProcessName;



	int len = GetModuleFileName(hInst,ProcessName.GetBuffer(256),256);

	if(len == 0)

	{

		MessageBox(NULL,"无法获取进程的当前目录","Error",0);

		return;	

	}

	ProcessName.ReleaseBuffer(len);





	DWORD direcLen = ProcessName.GetLength() + 1;

	LPBYTE direc = new BYTE[direcLen];

	ZeroMemory(direc,direcLen);



	ret = RegQueryValueEx(hKey,"VirtualDesk",0,0,direc,&direcLen);



	//如果键不存在或者键长度与目前的值长度不匹配则添加新键

	if((ret != ERROR_SUCCESS )|| (direcLen != ProcessName.GetLength()+1))

	{

SetValue:

		DWORD KeyLength = ProcessName.GetLength() + 1;

		LPBYTE KeyValue = new BYTE[KeyLength];

		ZeroMemory(KeyValue,KeyLength);



		for(int i=0;i<ProcessName.GetLength();i++)

			KeyValue[i] = ProcessName[i];



		KeyValue[ProcessName.GetLength()] = 0;



		ret = RegSetValueEx(hKey,"VirtualDesk",0,REG_SZ,KeyValue,KeyLength);			



		delete []KeyValue;



	}

	else

	{

		//如果键的内容与当前值不匹配同样进行更改

		for(int i=0;i<ProcessName.GetLength();i++)

		{

			if(direc[i] != ProcessName[i])

				goto SetValue;

		}



	}



	delete []direc;

	return;



}

//创建explorer进程的函数，如果创建了一个虚拟桌面，那么最好调用该函数

void StartExplorer()

{

	STARTUPINFO si;



	ZeroMemory( &si, sizeof(si) );

	si.cb = sizeof(si);

	si.lpDesktop = "Virtual";

	ZeroMemory( &piExplor, sizeof(piExplor) );



	if( !CreateProcess( NULL,	                                                                 // No module name (use command line). 

    "explorer",					                      // Command line. 

    NULL,						// Process handle not inheritable. 

    NULL,						// Thread handle not inheritable. 

    FALSE,						// Set handle inheritance to FALSE. 

    0,						// No creation flags. 

    NULL,						// Use parent's environment block. 

    NULL,						// Use parent's starting directory. 

    &si,						// Pointer to STARTUPINFO structure.

    &piExplor )						// Pointer to PROCESS_INFORMATION structure.

	) 

	{

		MessageBox(NULL,"无法初始化Explorer","Error",0);

		ExitProcess(1);

	}

}



ATOM MyRegisterClass(HINSTANCE hInstance)

{

 	WNDCLASSEX wcex;



	wcex.cbSize = sizeof(WNDCLASSEX); 



	wcex.style			= CS_HREDRAW | CS_VREDRAW;

	wcex.lpfnWndProc	= (WNDPROC)WndProc;

	wcex.cbClsExtra		= 0;

	wcex.cbWndExtra		= 0;

	wcex.hInstance		= hInstance;

	wcex.hIcon			= LoadIcon(hInstance, (LPCTSTR)IDI_APPLICATION);

	wcex.hCursor		= LoadCursor(NULL, IDC_ARROW);

	wcex.hbrBackground	= (HBRUSH)(COLOR_WINDOW+1);

	wcex.lpszMenuName	= NULL;

	wcex.lpszClassName	= szAppName;

	wcex.hIconSm		= LoadIcon(wcex.hInstance, (LPCTSTR)IDI_APPLICATION);



	return RegisterClassEx(&wcex);

}



BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)

{



   hInst = hInstance; // 将实例句柄存储在全局变量中



   hwnd = CreateWindow(szAppName, TEXT ("SunBear"), WS_OVERLAPPEDWINDOW,

      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInst, NULL);



   if (!hwnd)

   {

      return FALSE;

   }



   return TRUE;

}

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,

                    PSTR szCmdLine, int iCmdShow)

{

    static TCHAR szAppName[] = TEXT ("SunBear") ;

    MSG          msg ;



	SetStartup(hInstance);



	hVirtualDesk = CreateDesktop(

			"Virtual",

			NULL,

			NULL,

			DF_ALLOWOTHERACCOUNTHOOK,

			GENERIC_ALL,

			NULL);



	hCurrent = GetThreadDesktop(GetCurrentThreadId());



	MyRegisterClass(hInstance);

	if (!InitInstance (hInstance, iCmdShow)) 

	{

		return FALSE;

	}



	StartExplorer();			//启动Explorer进程

     

	if(!RegisterHotKey(hwnd, 0x0001,MOD_ALT ,'Q'))

	{

		//处理切换虚拟桌面

		return TRUE;

	}

	if(!RegisterHotKey(hwnd, 0x0002, 0,VK_F8))

	{

		//处理退出进程

		return TRUE;

	}

     while (GetMessage (&msg, NULL, 0, 0))

     {

          TranslateMessage (&msg) ;

          DispatchMessage (&msg) ;

     }

     return 0;

}



LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)

{

     HDC         hdc ;

     PAINTSTRUCT ps ;

     static HDESK hNow = hCurrent;



     switch (message)

     {    

     case WM_PAINT:

			hdc = BeginPaint (hwnd, &ps) ;

			EndPaint (hwnd, &ps) ;

			return 0 ;

          

     case WM_DESTROY:

			

			//在关闭虚拟桌面前要切换回当前桌面

			SwitchDesktop(hCurrent);

			PostQuitMessage (0) ;

			return 0 ;

     case WM_HOTKEY:

			if(0x0001 == wParam)

			{

				if(hNow == hCurrent)

				{

					SwitchDesktop(hVirtualDesk);

					hNow = hVirtualDesk;

				}

				else

				{

					SwitchDesktop(hCurrent);

					hNow = hCurrent;

				}

			}

			if(0x0002 == wParam)

			{



				//用TerminateProcess终止explorer进程的时候，如果传递第二个参数为1

				//那么操作系统不会在终止后自动唤醒explorer,如果为0,会重新启动

				//explorer

				TerminateProcess(piExplor.hProcess,1);



				//关闭虚拟桌面

				CloseDesktop(hVirtualDesk);



				SendMessage(hwnd,WM_CLOSE,0,0);

			}

			return 0;

	 }

     return DefWindowProc (hwnd, message, wParam, lParam) ;

}