wince下截屏的问题

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wince下截屏的问题 [复制链接]

以下代码，如果我想截一块区域的屏，应该在哪里更改数值？应该不是位图宽度和高度吧




HDC hScrDC,  hMemDC;        //屏幕和内存设备描述表      
HBITMAP hBitmap,  hOldBitmap;//位图句柄      
int nX,  nY,  nX2,  nY2;  //选定区域坐标      
int nWidth,  nHeight;        //位图宽度和高度      
int xScrn,  yScrn;          //屏幕分辨率  
   
//为屏幕创建设备描述表  
hScrDC  =  CreateDC(L"DISPLAY",  NULL,  NULL,  NULL);  

// CPaintDC dc(this);
// hScrDC = dc.GetSafeHdc();
//
   
//  获得屏幕分辨率  
xScrn  =  GetDeviceCaps(hScrDC,  HORZRES);  
yScrn  =  GetDeviceCaps(hScrDC,  VERTRES);  
   
//  确保选定区域不为空矩形  
if  (!lpRect  ||  IsRectEmpty(lpRect))  
{  
nX  =  0;  
nY  =  0;  
nX2  =  xScrn;  
nY2  =  yScrn;  
}  
else  
{  
//  获得选定区域坐标  
nX  =  lpRect->left;  
nY  =  lpRect->top;  
nX2  =  lpRect->right;  
nY2  =  lpRect->bottom;  

//确保选定区域是可见的  
if  (nX  <  0) nX  =  0;  
if  (nY  <  0) nY  =  0;  
if  (nX2  >  xScrn) nX2  =  xScrn;  
if  (nY2  >  yScrn) nY2  =  yScrn;  
}  
nWidth  = nX2 - nX;  
nHeight = nY2 - nY;  
   
//为屏幕设备描述表创建兼容的内存设备描述表  
hMemDC  =  CreateCompatibleDC(hScrDC);  
   
//创建一个与屏幕设备描述表兼容的位图  
hBitmap =  CreateCompatibleBitmap (hScrDC, nWidth, nHeight);  
   
//把新位图选到内存设备描述表中  
// hOldBitmap = (HBITMAP)SelectObject(hMemDC, hBitmap);  
   
//  把屏幕设备描述表拷贝到内存设备描述表中  
// BitBlt(hMemDC, 0, 0, nWidth, nHeight,hScrDC, nX, nY, SRCCOPY);  
   
//TextOut(hMemDC,100, 100,L"Rigel",sizeof("Rigel"));  
   
BYTE *lpBitmapBits = NULL;

BITMAPINFO RGB24BitsBITMAPINFO;
ZeroMemory(&RGB24BitsBITMAPINFO, sizeof(BITMAPINFO));
RGB24BitsBITMAPINFO.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
    RGB24BitsBITMAPINFO.bmiHeader.biWidth = nWidth;
    RGB24BitsBITMAPINFO.bmiHeader.biHeight = nHeight;
    RGB24BitsBITMAPINFO.bmiHeader.biPlanes = 1;
    RGB24BitsBITMAPINFO.bmiHeader.biBitCount = 24;

//得到屏幕位图的句柄  
// hBitmap = (HBITMAP)SelectObject(hMemDC, hOldBitmap);  

    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, nWidth, nHeight, hScrDC, nX, nY, 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;

//bimap 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 + ((nWidth*nHeight)*3); ///3=(24 / 8)

//write into file
FILE *mStream = NULL;
if((mStream = fopen(filename, "wb")))
{  
//write bitmap file header
fwrite(&bmBITMAPFILEHEADER, sizeof(BITMAPFILEHEADER), 1, mStream);
//write bitmap info
fwrite(&(RGB24BitsBITMAPINFO.bmiHeader), sizeof(BITMAPINFOHEADER), 1, mStream);
//write bitmap pixels data
fwrite(lpBitmapBits, 3*nWidth*nHeight, 1, mStream);
//close file
fclose(mStream);
}
   
//清除   
DeleteDC(hScrDC);  
DeleteDC(hMemDC);  

yuanju188

BitBlt(hMemDC, 0, 0, nWidth, nHeight, hScrDC, nX, nY, SRCCOPY);

修改这个里面的nX、nY、nWidth和nHeight，别的地方可能也需要稍微改动一下。

dfghfhfhgf

就几个参数改一下，试一下就知道了