[收藏]IPicture::SaveAsFile的一个使用例子

天云上人

  BOOL CPicture::SaveAsBitmap(CString sFilePathName)
//=============================================================================
{
BOOL bResult = FALSE;
ILockBytes *Buffer = 0;
IStorage   *pStorage = 0;
3 x% t) Z' \/ x$ Z IStream    *FileStream = 0;
BYTE    *BufferBytes;
STATSTG  BytesStatistics;
DWORD  OutData;
long  OutStream;
& \7 i5 p8 U2 M5 W/ K, O  k" e$ C CFile  BitmapFile; CFileException e;
double  SkipFloat = 0;
2 \7 E  R9 |! G: ` DWORD  ByteSkip = 0;
_ULARGE_INTEGER RealData;
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CreateILockBytesOnHGlobal(NULL, TRUE, &Buffer); // Create ILockBytes Buffer
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HRESULT hr = ::StgCreateDocfileOnILockBytes(Buffer,
    STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, &pStorage);



% {1 U$ K( i* q: b$ b+ y6 i2 F& m hr = pStorage->CreateStream(LPICTURE,
  STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, 0, &FileStream);
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5 a0 f6 p4 b6 `; b  O2 k4 S m_pPict->SaveAsFile(FileStream, TRUE, &OutStream); // Copy Data Stream
# k( ]# ~3 D- z: @3 o- r7 M! { FileStream->Release();
pStorage->Release();
# k+ |5 n) k7 Y" t' C: N Buffer->Flush();
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, S( h) C) H. ~7 w9 f0 ~ // Get Statistics For Final Size Of Byte Array
0 D% T  e4 J# q! V Buffer->Stat(&BytesStatistics, STATFLAG_NONAME);
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// Cut UnNeeded Data Coming From SaveAsFile() (Leave Only Pure Picture Data)
SkipFloat = (double(OutStream) / 512); // Must Be In a 512 Blocks...
' R- [  U5 R( K4 D; O- o0 l4 c if(SkipFloat > DWORD(SkipFloat)) ByteSkip = (DWORD)SkipFloat + 1;
/ `$ @# w6 l- Q/ A2 R else ByteSkip = (DWORD)SkipFloat;
ByteSkip = ByteSkip * 512; // Must Be In a 512 Blocks...

// Find Difference Between The Two Values
ByteSkip = (DWORD)(BytesStatistics.cbSize.QuadPart - ByteSkip);
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// Allocate Only The Pure Picture Data
RealData.LowPart = 0;
$ r$ y1 H3 _$ r- ^5 z RealData.HighPart = 0;
6 V$ O$ B& u& i( z+ `3 @ RealData.QuadPart = ByteSkip;
BufferBytes = (BYTE*)malloc(OutStream);
5 Q- O! \3 ?9 ^4 Z1 u6 Z if(BufferBytes == NULL)
  {
  Buffer->Release();
" W  B0 W' S" j( A$ R# S3 U4 I% D: _  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
5 ~0 k: V+ P- g0 u' _, @  a0 _  MessageBoxEx(hWnd, Can not allocate enough memory\\t, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
  }
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. g6 x$ s, F+ B6 {! @' t: h Buffer->ReadAt(RealData, BufferBytes, OutStream, &OutData);
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if(BitmapFile.Open(sFilePathName, CFile::typeBinary | CFile::modeCreate | CFile::modeWrite, &e))
8 n3 L% a+ m# u* s% @6 r  {
  BitmapFile.Write(BufferBytes, OutData);
, F+ [" t/ j+ @  `* |  BitmapFile.Close();
% v2 N5 P' N5 D: i; s  bResult = TRUE;
' R8 v% k* D9 x/ y& j  t  }
else // Write File Failed...
  {
" {, B4 u8 S- W* j  TCHAR szCause[255];
  e.GetErrorMessage(szCause, 255, NULL);
  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
: y* N7 x' K: i4 w' H) U( z+ J  MessageBoxEx(hWnd, szCause, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
% ~# Z& a% R9 c3 y6 E2 U% J/ Q7 i3 J  bResult = FALSE;
% y3 @8 f. Z8 |+ @0 k' A  }

5 J  p4 ]2 @9 T, E! i# Y; c1 ~ Buffer->Release();
free(BufferBytes);

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return(bResult);
}