不使用CFileDialog类产生保存和打开对话框的代码(直接拷贝)

最新推荐文章于 2022-09-16 21:05:45 发布

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#colors #null #structure #hp #file #bi

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本文详细介绍了如何使用Windows API创建一个BMP文件并生成对应的位图文件，包括获取位图信息、创建BITMAPINFO结构、计算位图大小、写入文件等关键步骤。

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#ifdef _DEBUG
#define errhandler(msg,h) printf("Error Message: %s, HWND is %x ",msg, h)
#else
#define errhandler(msg,h)
#endif

PBITMAPINFO   CreateBitmapInfoStruct(HWND   hwnd,   HBITMAP   hBmp)
{
BITMAP   bmp;
PBITMAPINFO   pbmi;
WORD         cClrBits;

//   Retrieve   the   bitmap 's   color   format,   width,   and   height.
if   (! GetObject(hBmp,   sizeof(BITMAP),   (LPSTR)&bmp) )
  errhandler( "GetObject ",   hwnd);

//   Convert   the   color   format   to   a   count   of   bits.
cClrBits   =   (WORD)(bmp.bmPlanes   *   bmp.bmBitsPixel);
if   (cClrBits   ==   1)
  cClrBits   =   1;
else   if   (cClrBits   <=   4)
  cClrBits   =   4;
else   if   (cClrBits   <=   8)
  cClrBits   =   8;
else   if   (cClrBits   <=   16)
  cClrBits   =   16;
else   if   (cClrBits   <=   24)
  cClrBits   =   24;
else   cClrBits   =   32;

//   Allocate   memory   for   the   BITMAPINFO   structure.   (This   structure
//   contains   a   BITMAPINFOHEADER   structure   and   an   array   of   RGBQUAD
//   data   structures.)

if   (cClrBits   !=   24)
  pbmi   =   (PBITMAPINFO)   LocalAlloc(LPTR,
  sizeof(BITMAPINFOHEADER)
  +sizeof(RGBQUAD)*(1<< cClrBits));

// There is no RGBQUAD array for the 24-bit-per-pixel format.

else
  pbmi   =   (PBITMAPINFO)   LocalAlloc(LPTR,
  sizeof(BITMAPINFOHEADER));

// Initialize the fields in the BITMAPINFO structure.

pbmi-> bmiHeader.biSize   =   sizeof(BITMAPINFOHEADER);
pbmi-> bmiHeader.biWidth   =   bmp.bmWidth;
pbmi-> bmiHeader.biHeight   =   bmp.bmHeight;
pbmi-> bmiHeader.biPlanes   =   bmp.bmPlanes;
pbmi-> bmiHeader.biBitCount   =   bmp.bmBitsPixel;
if   (cClrBits   <   24)
  pbmi-> bmiHeader.biClrUsed   =   (1 <<cClrBits);

// If the bitmap is not compressed, set the BI_RGB flag.
pbmi-> bmiHeader.biCompression = BI_RGB;

//   Compute   the   number   of   bytes   in   the   array   of   color
//   indices   and   store   the   result   in   biSizeImage.
pbmi-> bmiHeader.biSizeImage   =   (pbmi-> bmiHeader.biWidth   +   7)/8
  *   pbmi-> bmiHeader.biHeight*cClrBits;
//   Set   biClrImportant   to   0,   indicating   that   all   of   the
//   device   colors   are   important.
pbmi-> bmiHeader.biClrImportant   =   0;
return   pbmi;
}

void   CreateBMPFile(HWND   hwnd,   LPTSTR   pszFile,   PBITMAPINFO   pbi,
      HBITMAP   hBMP,   HDC   hDC)
{
HANDLE   hf;                                   //   file   handle
BITMAPFILEHEADER   hdr;               //   bitmap   file-header
PBITMAPINFOHEADER   pbih;           //   bitmap   info-header
LPBYTE   lpBits;                             //   memory   pointer
DWORD   dwTotal;                             //   total   count   of   bytes
DWORD   cb;                                       //   incremental   count   of   bytes
BYTE   *hp;                                       //   byte   pointer
DWORD   dwTmp;

pbih = (PBITMAPINFOHEADER) pbi;
lpBits = (LPBYTE) GlobalAlloc(GMEM_FIXED, pbih-> biSizeImage);

if (!lpBits)
errhandler( "GlobalAlloc ", hwnd);

//   Retrieve   the   color   table   (RGBQUAD   array)   and   the   bits
//   (array   of   palette   indices)   from   the   DIB.
if   (!GetDIBits(hDC,   hBMP,   0,   (WORD)   pbih-> biHeight,   lpBits,   pbi,
  DIB_RGB_COLORS))
{
  errhandler( "GetDIBits ",   hwnd);
}

//   Create   the   .BMP   file.
hf   =   CreateFile(pszFile,
  GENERIC_READ   |   GENERIC_WRITE,
  (DWORD)   0,
  NULL,
  CREATE_ALWAYS,
  FILE_ATTRIBUTE_NORMAL,
  (HANDLE)   NULL);
if   (hf   ==   INVALID_HANDLE_VALUE)
  errhandler( "CreateFile ",   hwnd);
hdr.bfType   =   0x4d42;                 //   0x42   =   "B "   0x4d   =   "M "
//   Compute   the   size   of   the   entire   file.
hdr.bfSize   =   (DWORD)   (sizeof(BITMAPFILEHEADER)   +
  pbih-> biSize   +   pbih-> biClrUsed
  *   sizeof(RGBQUAD)   +   pbih-> biSizeImage);
hdr.bfReserved1   =   0;
hdr.bfReserved2   =   0;

//   Compute   the   offset   to   the   array   of   color   indices.
hdr.bfOffBits   =   (DWORD)   sizeof(BITMAPFILEHEADER)   +
  pbih-> biSize   +   pbih-> biClrUsed
  *   sizeof   (RGBQUAD);

//   Copy   the   BITMAPFILEHEADER   into   the   .BMP   file.
if   (!WriteFile(hf,   (LPVOID)   &hdr,   sizeof(BITMAPFILEHEADER),
  (LPDWORD)   &dwTmp,     NULL))
{
  errhandler( "WriteFile ",   hwnd);
}

//   Copy   the   BITMAPINFOHEADER   and   RGBQUAD   array   into   the   file.
if(!WriteFile(hf,   (LPVOID)   pbih,   sizeof(BITMAPINFOHEADER)
  +   pbih-> biClrUsed   *   sizeof   (RGBQUAD), (LPDWORD)   &dwTmp,   (   NULL)) )
  errhandler( "WriteFile ",   hwnd);

//   Copy   the   array   of   color   indices   into   the   .BMP   file.
dwTotal   =   cb   =   pbih-> biSizeImage;
hp   =   lpBits;
if   (!WriteFile(hf,   (LPSTR)   hp,   (int)   cb,   (LPDWORD)   &dwTmp,NULL))
  errhandler( "WriteFile ",   hwnd);

//   Close   the   .BMP   file.
if   (!CloseHandle(hf))
  errhandler( "CloseHandle ",   hwnd);

// Free memory.
GlobalFree((HGLOBAL)lpBits);
}
///////////////////////////////////////////////////////////////////////////////////////////