[收藏]IPicture::SaveAsFile的一个使用例子

天云上人

  BOOL CPicture::SaveAsBitmap(CString sFilePathName)
//=============================================================================
% p5 q- s/ T- j{
6 ?/ c6 {+ w6 }( _4 }) E BOOL bResult = FALSE;
. @5 J: o5 s2 Y* b! u ILockBytes *Buffer = 0;
IStorage   *pStorage = 0;
IStream    *FileStream = 0;
BYTE    *BufferBytes;
STATSTG  BytesStatistics;
DWORD  OutData;
long  OutStream;
CFile  BitmapFile; CFileException e;
double  SkipFloat = 0;
; s# p4 o' I; a- I& p/ l7 @ DWORD  ByteSkip = 0;
_ULARGE_INTEGER RealData;
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CreateILockBytesOnHGlobal(NULL, TRUE, &Buffer); // Create ILockBytes Buffer
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8 ^9 E( z8 D& m0 K, \1 N; x  c8 J 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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3 U- G8 G6 A' T' P0 a m_pPict->SaveAsFile(FileStream, TRUE, &OutStream); // Copy Data Stream
, z$ K2 Q( F4 j  V! k6 R; A3 D# 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)
7 ^7 e+ y0 c, j# D9 M- g2 ?" W, \3 z SkipFloat = (double(OutStream) / 512); // Must Be In a 512 Blocks...
if(SkipFloat > DWORD(SkipFloat)) ByteSkip = (DWORD)SkipFloat + 1;
else ByteSkip = (DWORD)SkipFloat;
# l# ?1 Y3 _" l, Y6 b4 v: C. A ByteSkip = ByteSkip * 512; // Must Be In a 512 Blocks...

// Find Difference Between The Two Values
! J' w* A& U( u0 _ ByteSkip = (DWORD)(BytesStatistics.cbSize.QuadPart - ByteSkip);
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% s- J. w1 Q- i/ V- U4 H // Allocate Only The Pure Picture Data
RealData.LowPart = 0;
# }# c' o: ^& {6 q) I RealData.HighPart = 0;
RealData.QuadPart = ByteSkip;
BufferBytes = (BYTE*)malloc(OutStream);
" p0 N3 S" k% J4 g9 N. d, q if(BufferBytes == NULL)
  {
- v  h+ A+ J4 N' T, _: y  Buffer->Release();
  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
  MessageBoxEx(hWnd, Can not allocate enough memory\\t, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
" y/ U) Z7 I, t3 ^- i6 m+ h5 V  }


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" _* o# ]$ l1 ] Buffer->ReadAt(RealData, BufferBytes, OutStream, &OutData);

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if(BitmapFile.Open(sFilePathName, CFile::typeBinary | CFile::modeCreate | CFile::modeWrite, &e))
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) |' x3 W4 ~3 J; @' B8 N  BitmapFile.Write(BufferBytes, OutData);
) k% d8 W. ?' e6 F; o% L  BitmapFile.Close();
  bResult = TRUE;
6 J" N' k# o; P' M  }  }
- ^* {, |& g' G# \ else // Write File Failed...
1 b0 _- x+ s# X+ [$ z7 Z: U  {
  TCHAR szCause[255];
  e.GetErrorMessage(szCause, 255, NULL);
1 i+ Z3 p( l$ [) [# b0 M  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
  MessageBoxEx(hWnd, szCause, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
' T. T& M! n' z; Q& S# w; h  bResult = FALSE;
5 g2 c) a  P5 ]0 p/ m: r3 o  }
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: P1 z/ {6 V% z/ Y8 T3 _, c7 j$ r Buffer->Release();
* C* x- k6 d/ N! X. l8 ? free(BufferBytes);
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return(bResult);
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