[收藏]IPicture::SaveAsFile的一个使用例子

天云上人

  BOOL CPicture::SaveAsBitmap(CString sFilePathName)
//=============================================================================
{
! c7 E7 y9 q& N' j+ p2 k* K BOOL bResult = FALSE;
) z& V' z9 d. a& y) } ILockBytes *Buffer = 0;
" @6 D. c. X6 @9 d1 b IStorage   *pStorage = 0;
: |! q1 j5 t" m; c! l+ w- q IStream    *FileStream = 0;
BYTE    *BufferBytes;
STATSTG  BytesStatistics;
) W& L- G9 z3 v5 ]  n' `2 [ DWORD  OutData;
. z7 X$ c* r1 x1 G5 _7 v) y( N long  OutStream;
CFile  BitmapFile; CFileException e;
double  SkipFloat = 0;
$ g: K6 @8 }0 Y8 h4 `% j 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);
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hr = pStorage->CreateStream(LPICTURE,
  STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, 0, &FileStream);

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m_pPict->SaveAsFile(FileStream, TRUE, &OutStream); // Copy Data Stream
) F' Q$ \) y$ a0 ~- A FileStream->Release();
pStorage->Release();
Buffer->Flush();
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// Get Statistics For Final Size Of Byte Array
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...
if(SkipFloat > DWORD(SkipFloat)) ByteSkip = (DWORD)SkipFloat + 1;
7 L3 _. l7 A) H0 a" `: j' D9 U0 Y else ByteSkip = (DWORD)SkipFloat;
; n; o, Y) @. p" }5 H ByteSkip = ByteSkip * 512; // Must Be In a 512 Blocks...

// Find Difference Between The Two Values
& j4 D  P) ?8 U: v# r ByteSkip = (DWORD)(BytesStatistics.cbSize.QuadPart - ByteSkip);

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' f6 I0 `. L/ x' f9 L! S( M' t" R // Allocate Only The Pure Picture Data
5 H- ?! h' P8 x RealData.LowPart = 0;
+ I6 r: E1 x4 t3 L. x8 Z5 `/ j RealData.HighPart = 0;
( d& r% l* o7 V# v, { RealData.QuadPart = ByteSkip;
9 E9 y5 O! ~+ A# f0 F3 V- z# c/ b6 f' i BufferBytes = (BYTE*)malloc(OutStream);
" D& x& J5 ]& ~' L5 J if(BufferBytes == NULL)
- H$ F/ Y8 ?: s0 P5 z  {
& T5 }! |9 Q8 z% ^: Q4 O  Buffer->Release();
6 ^+ b$ W4 t9 `# @  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
: E0 ?( W* S! u0 A! g6 r  MessageBoxEx(hWnd, Can not allocate enough memory\\t, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
  }

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Buffer->ReadAt(RealData, BufferBytes, OutStream, &OutData);
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& O( o! `9 P" R! y+ f5 m if(BitmapFile.Open(sFilePathName, CFile::typeBinary | CFile::modeCreate | CFile::modeWrite, &e))
4 c! U: [. r& n0 Q  d" h3 y  {
  BitmapFile.Write(BufferBytes, OutData);
* k2 g( M$ R/ v+ Q6 M$ ^- q  BitmapFile.Close();
. d9 M5 I' v/ S2 x+ B% q3 o5 Q  bResult = TRUE;
2 N/ y* ^7 E6 s1 V5 O( g! F  }
# k) j; B2 N* i+ t# L( e5 ` else // Write File Failed...
  {
2 T& T6 o" F3 T* B+ T$ T! \1 e  TCHAR szCause[255];
  e.GetErrorMessage(szCause, 255, NULL);
+ k  r; B# N) L+ P1 ?0 c& L  z  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
  MessageBoxEx(hWnd, szCause, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
  bResult = FALSE;
  }
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5 F& k4 |* Y' _. L9 I' q' d Buffer->Release();
free(BufferBytes);

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9 I4 M% `. P$ O, `  D return(bResult);
}