SDK 방식으로 화면을 캡처하여 BMP 형식으로 저장합니다.

인터넷 MFC의 예는 적지 않다.BHO 하나 쓸 때 안 되는 게 많아요. 다음은 순수SDK 방식으로 썼어요.
함수 이름 표시 함수 기능

//    
void Screenshots()
{
	HBITMAP	hDesktopCompatibleBitmap=NULL;
	HDC		hDesktopCompatibleDC=NULL;
	HDC		hDesktopDC=NULL;
	HWND		hDesktopWnd=NULL;
	RECT		clientRect = {0,0,0,0};
	NOTIFYICONDATA	nid;

	bool bMinimized=false;

	int wmId, wmEvent;
	PAINTSTRUCT ps;
	HDC hdc;

	OPENFILENAME	ofn;
	char	szFileName[512]; 

	strcpy(szFileName,"J://ScreenShot.bmp");

	ZeroMemory(&ofn,sizeof(ofn));
	ofn.lStructSize=sizeof(OPENFILENAME);
	ofn.Flags=OFN_HIDEREADONLY|OFN_PATHMUSTEXIST;
	ofn.lpstrFilter="Bitmap Files (*.bmp)/0*.bmp/0";
	ofn.lpstrDefExt="bmp";
	ofn.lpstrFile=szFileName;
	ofn.nMaxFile=512;
//	ofn.hwndOwner = hWnd;
// 	if(!GetSaveFileName(&ofn))	
// 		return;

	SetCursor(LoadCursor(NULL,IDC_WAIT));	
	int		nWidth=GetSystemMetrics(SM_CXSCREEN);
	int		nHeight=GetSystemMetrics(SM_CYSCREEN);

	hDesktopDC = CreateDC("DISPLAY", NULL, NULL, NULL); 
	HDC		hBmpFileDC=CreateCompatibleDC(hDesktopDC);
	HBITMAP	hBmpFileBitmap=CreateCompatibleBitmap(hDesktopDC,nWidth,nHeight);
	HBITMAP hOldBitmap = (HBITMAP) SelectObject(hBmpFileDC,hBmpFileBitmap);
	BitBlt(hBmpFileDC,0,0,nWidth,nHeight,hDesktopDC,0,0,SRCCOPY|CAPTUREBLT);
	SelectObject(hBmpFileDC,hOldBitmap);

	SaveBitmap(ofn.lpstrFile,hBmpFileBitmap);

	DeleteDC(hBmpFileDC);
	DeleteObject(hBmpFileBitmap);
	SetCursor(LoadCursor(NULL,IDC_ARROW));

}

//        Bmp  
//szFile     
void	SaveBitmap(char *szFilename,HBITMAP hBitmap)
{
	HDC					hdc=NULL;
	FILE*				fp=NULL;
	LPVOID				pBuf=NULL;
	BITMAPINFO			bmpInfo;
	BITMAPFILEHEADER	bmpFileHeader;
	
	do{
		
		hdc=GetDC(NULL);
		ZeroMemory(&bmpInfo,sizeof(BITMAPINFO));
		bmpInfo.bmiHeader.biSize=sizeof(BITMAPINFOHEADER);
		GetDIBits(hdc,hBitmap,0,0,NULL,&bmpInfo,DIB_RGB_COLORS);
		
		if(bmpInfo.bmiHeader.biSizeImage<=0)
			bmpInfo.bmiHeader.biSizeImage=bmpInfo.bmiHeader.biWidth*abs(bmpInfo.bmiHeader.biHeight)*(bmpInfo.bmiHeader.biBitCount+7)/8;
		
		if((pBuf=malloc(bmpInfo.bmiHeader.biSizeImage))==NULL)
		{
//			MessageBox(NULL,_T("Unable to Allocate Bitmap Memory"),_T("Error"),MB_OK|MB_ICONERROR);
			break;
		}
		
		bmpInfo.bmiHeader.biCompression=BI_RGB;
		GetDIBits(hdc,hBitmap,0,bmpInfo.bmiHeader.biHeight,pBuf,&bmpInfo,DIB_RGB_COLORS);	
		
		if((fp=fopen(szFilename,"wb"))==NULL)
		{
		//	MessageBox(NULL,_T("Unable to Create Bitmap File"),_T("Error"),MB_OK|MB_ICONERROR);
			break;
		}
		
		bmpFileHeader.bfReserved1=0;
		bmpFileHeader.bfReserved2=0;
		bmpFileHeader.bfSize=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER)+bmpInfo.bmiHeader.biSizeImage;
		bmpFileHeader.bfType='MB';
		bmpFileHeader.bfOffBits=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER);
		
		fwrite(&bmpFileHeader,sizeof(BITMAPFILEHEADER),1,fp);
		fwrite(&bmpInfo.bmiHeader,sizeof(BITMAPINFOHEADER),1,fp);
		fwrite(pBuf,bmpInfo.bmiHeader.biSizeImage,1,fp);
		
	}while(false);
	
	if(hdc)
		ReleaseDC(NULL,hdc);
	
	if(pBuf)
		free(pBuf);
	
	if(fp)
		fclose(fp);
}