[收藏]IPicture::SaveAsFile的一个使用例子

天云上人

  BOOL CPicture::SaveAsBitmap(CString sFilePathName)
//=============================================================================
# [+ ~0 z$ s5 L$ D# B8 C{
# k3 h) d3 [3 p# I& |, }7 q BOOL bResult = FALSE;
ILockBytes *Buffer = 0;
: c' F& v" J) H- a" L7 |' M IStorage   *pStorage = 0;
IStream    *FileStream = 0;
BYTE    *BufferBytes;
4 r) k6 [+ i0 S! y* j STATSTG  BytesStatistics;
# c4 |, K: T/ y$ g5 X DWORD  OutData;
: f5 f: [5 }, w3 T long  OutStream;
+ N' t, b3 i  `. i/ ~- z& r CFile  BitmapFile; CFileException e;
double  SkipFloat = 0;
DWORD  ByteSkip = 0;
5 m& r- I( @: }3 o+ l5 H+ R/ I _ULARGE_INTEGER RealData;

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! P8 H+ L: R9 I CreateILockBytesOnHGlobal(NULL, TRUE, &Buffer); // Create ILockBytes Buffer
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HRESULT hr = ::StgCreateDocfileOnILockBytes(Buffer,
5 y8 f' _) ^4 I- ?9 ^" @     STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, &pStorage);
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hr = pStorage->CreateStream(LPICTURE,
' N2 A" s; V* F% S   STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, 0, &FileStream);

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* O( H: c" m% U/ a) m$ P m_pPict->SaveAsFile(FileStream, TRUE, &OutStream); // Copy Data Stream
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)
; }; s7 d' e9 w% L4 F# y3 v SkipFloat = (double(OutStream) / 512); // Must Be In a 512 Blocks...
2 @' k' _) p% ]" g  _. N2 i- Q if(SkipFloat > DWORD(SkipFloat)) ByteSkip = (DWORD)SkipFloat + 1;
/ z4 B6 \1 S, X0 p& M2 g* { else ByteSkip = (DWORD)SkipFloat;
ByteSkip = ByteSkip * 512; // Must Be In a 512 Blocks...

// Find Difference Between The Two Values
$ |! u* P! W$ {6 U( t6 y ByteSkip = (DWORD)(BytesStatistics.cbSize.QuadPart - ByteSkip);

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7 ?2 W  o, p2 P, C. } // Allocate Only The Pure Picture Data
& s: l0 J0 z" {$ b- u RealData.LowPart = 0;
: K" \2 c9 f6 ~2 u" F" s& q/ j RealData.HighPart = 0;
% Y# v$ V, [9 J& _. i RealData.QuadPart = ByteSkip;
BufferBytes = (BYTE*)malloc(OutStream);
  R2 }7 H: K: H0 H" k- u% [ if(BufferBytes == NULL)
  {
  Buffer->Release();
) ^# ?: K6 O3 q, z2 y$ s6 F  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
  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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if(BitmapFile.Open(sFilePathName, CFile::typeBinary | CFile::modeCreate | CFile::modeWrite, &e))
  {
  BitmapFile.Write(BufferBytes, OutData);
" W5 m* v" g2 E: F/ S  BitmapFile.Close();
  bResult = TRUE;
( b3 q* j! {2 ]- W' L* n  }
1 b7 J6 P4 ]9 P" Z! g4 d else // Write File Failed...
  {
" q/ x( ?/ k& d1 a9 z" M% }  TCHAR szCause[255];
% q- N) G! M4 S* t) z, p- l' ?3 g  e.GetErrorMessage(szCause, 255, NULL);
  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
  MessageBoxEx(hWnd, szCause, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
: r1 c: s+ R0 q  y* w1 }2 k; P  bResult = FALSE;
; ]/ ^- X1 [9 b) U5 ]  }

7 x. X4 {  _4 l0 C: I4 y Buffer->Release();
free(BufferBytes);
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return(bResult);
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