屏幕截图

我想做一个屏幕截图程序，然后保存在硬盘中。大家能否赐教啊。

这个简单，有截屏的函数的

http://www.cnblogs.com/projectdevelop/archive/2009/06/08/1498476.html

不好意思，我以前见过是别人写的函数，API没有

BOOL CMpCurveAnalysisDlg::SaveCurBMP()
{
        int nResponse;
        CString strFileName;


    HDC hScrDC;
        HDC hMemDC;         
    int width=640;
        int height=445;

        //the pointer will save all pixel point's color value
        BYTE  *lpBitmapBits = NULL;
        
        //creates a device context for the screen device
    hScrDC = CreateDC(_T("DISPLAY"), NULL, NULL, NULL);
        //get the screen point size

    //width = GetDeviceCaps(hScrDC, HORZRES);
    //height = GetDeviceCaps(hScrDC, VERTRES);
        //width=lpRect->right-lpRect->left;
        //height=lpRect->bottom-lpRect->top;
        width=640;
        height=445;
       
    //creates a memory device context (DC) compatible with the screen device(hScrDC)  
    hMemDC = CreateCompatibleDC(hScrDC);
        //initialise the struct BITMAPINFO for the bimap infomation，
        //in order to use the function CreateDIBSection
        // on wince os, each pixel stored by 24 bits(biBitCount=24)
        //and no compressing(biCompression=0)
    BITMAPINFO RGB24BitsBITMAPINFO;
    ZeroMemory(&RGB24BitsBITMAPINFO, sizeof(BITMAPINFO));
    RGB24BitsBITMAPINFO.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
    RGB24BitsBITMAPINFO.bmiHeader.biWidth = width;
    RGB24BitsBITMAPINFO.bmiHeader.biHeight = height;
    RGB24BitsBITMAPINFO.bmiHeader.biPlanes = 1;
    RGB24BitsBITMAPINFO.bmiHeader.biBitCount = 24;
   
        //use the function CreateDIBSection and SelectObject
        //in order to get the bitmap pointer : lpBitmapBits

        HBITMAP directBmp = CreateDIBSection(hMemDC, (BITMAPINFO*)&RGB24BitsBITMAPINFO,
                                                                            DIB_RGB_COLORS, (void **)&lpBitmapBits, NULL, 0);
        HGDIOBJ previousObject = SelectObject(hMemDC, directBmp);
        // copy the screen dc to the memory dc
        //BitBlt(hMemDC, 0, 0, width, height, hScrDC, 0, 0, SRCCOPY);

        BitBlt(hMemDC,0, 0, width, height, hScrDC, 7,70,SRCCOPY);

        //if you only want to get the every pixel color value,
        //you can begin here and the following part of this function will be unuseful;
        //the following part is in order to write file;
        //bitmap file header in order to write bmp file
        BITMAPFILEHEADER bmBITMAPFILEHEADER;
        ZeroMemory(&bmBITMAPFILEHEADER, sizeof(BITMAPFILEHEADER));
        bmBITMAPFILEHEADER.bfType = 0x4d42;  //bmp  
        bmBITMAPFILEHEADER.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);
        bmBITMAPFILEHEADER.bfSize = bmBITMAPFILEHEADER.bfOffBits + ((width*height)*3); ///3=(24 / 8)

        //Windows 规定一个扫描行所占的字节数必须是4的倍数。
        //有可能宽度所占的像素字节数不是4的倍数，所以必须把它转换成4的倍数。

        //int iWidth=800;
        int iWidth=width;

        int iBitCount=24;
        //int iHeight=600;
        int iHeight=height;


        int DataSizePerLine=(iWidth*iBitCount+31)/8; //ensure the width is the multiple of 4
        int DataSize=DataSizePerLine*iHeight;//实际文件的大小
        //write into file

        CFile BmpFile;

///////////////////////////////////////////////////////////////////////////////////////////////



        CFileDialog dlgSaveCurBMP(TRUE,_T("bmp文件(*.bmp)|*.bmp||"),_T("CurveNO"),
                                      OFN_OVERWRITEPROMPT,_T("*.bmp||"),this);
        //m_dlgMpAlarmExport.Create();
        dlgSaveCurBMP.m_ofn.lpstrInitialDir=_T("\\硬盘\\CurveSave\\");
        nResponse=dlgSaveCurBMP.DoModal();
        if(nResponse==IDOK)
        {
        strFileName=dlgSaveCurBMP.GetPathName();
        }

        BmpFile.Open(strFileName,CFile::modeCreate|CFile::modeWrite,NULL);

        BmpFile.Write(&bmBITMAPFILEHEADER, sizeof(BITMAPFILEHEADER));

        BmpFile.Write(&(RGB24BitsBITMAPINFO.bmiHeader), sizeof(BITMAPINFOHEADER));

        BmpFile.Write(lpBitmapBits, DataSize);

        BmpFile.Close();

        //delete
        DeleteObject(hMemDC);
        DeleteObject(hScrDC);
        DeleteObject(directBmp);
        DeleteObject(previousObject);


        return TRUE;

}

我运行调试出现“Disk fullaccessing\NandFlash\Y.bmp"的对话框时怎么回事啊？   帮忙看看代码啊。
void Drawninformation::SaveDCToBMP(HDC hDC,int nStartX,int nStartY, int nWidth,int nHeight,LPCTSTR szFileName)
{
//定义图形色深
        int iPixel = 32;
//位图信息头
        LPBITMAPINFO lpbmih = new BITMAPINFO;
        lpbmih->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
        lpbmih->bmiHeader.biWidth = nWidth;
        lpbmih->bmiHeader.biHeight = nHeight;
        lpbmih->bmiHeader.biPlanes = 1;
        lpbmih->bmiHeader.biBitCount = iPixel;
        lpbmih->bmiHeader.biCompression = BI_RGB;
        lpbmih->bmiHeader.biSizeImage = 0;
        lpbmih->bmiHeader.biXPelsPerMeter = 0;
        lpbmih->bmiHeader.biYPelsPerMeter = 0;
        lpbmih->bmiHeader.biClrUsed = 0;
        lpbmih->bmiHeader.biClrImportant = 0;
//创建位图数据
        HDC hdcMem;
        HBITMAP hBitMap = NULL;
        CBitmap *pBitMap = NULL;
        CDC *pMemDC = NULL;
        BYTE *pBits = NULL;

         hdcMem = CreateCompatibleDC(hDC);
         hBitMap = CreateDIBSection(hdcMem,lpbmih,DIB_PAL_COLORS,(void **)&pBits,NULL,0);
         ////
         pBitMap = new CBitmap;
         pBitMap->Attach(hBitMap);
         ////
         pMemDC = new CDC;
         pMemDC->Attach(hdcMem);
         //CreateCompatibleBitmap
         ////
         pMemDC->SelectObject(pBitMap);
         pMemDC->BitBlt(0,0,nWidth,nHeight,CDC::FromHandle(hDC),nStartX,nStartY,SRCCOPY);
         BITMAPFILEHEADER bmfh;
         //位图文件头
         ZeroMemory(&bmfh,sizeof(BITMAPFILEHEADER));
         *((char *)&bmfh.bfType) = 'B';
         *(((char *)&bmfh.bfType) + 1) = 'M';
         bmfh.bfType = 0x4d42;  //bmp  
         bmfh.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);
        bmfh.bfSize = bmfh.bfOffBits + (nWidth * nHeight) * iPixel / 8;
         int iBMPBytes = nWidth * nHeight * iPixel / 8;
        /* bmfh.bfSize = (nWidth*32+31)/8;
         int iBMPBytes = bmfh.bfSize * nHeight;*/
         ////
         CFile file;
         if(file.Open(szFileName,CFile::modeWrite | CFile::modeCreate,NULL))
         {  
                 file.Write(&bmfh,sizeof(BITMAPFILEHEADER));
                 file.Write(&(lpbmih->bmiHeader),sizeof(BITMAPINFOHEADER));
                 file.Write(pBits,iBMPBytes);//在此处弹出对话框“Disk fullaccessing\NandFlash\Y.bmp"，还望大家能够帮忙看看



                 file.Close();
         }
         ////
         DeleteObject(hBitMap);
         DeleteObject(hDC);
         pMemDC->DeleteDC();
         delete pMemDC;
         pMemDC = NULL;
         delete pBitMap;
         pBitMap = NULL;
         delete lpbmih;
         lpbmih = NULL;

}