[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;
6 k' P, V7 @7 J, i  I" e IStream    *FileStream = 0;
" ^( D$ }' T' X2 D1 X  g BYTE    *BufferBytes;
STATSTG  BytesStatistics;
9 ?1 A: F( H! P& c/ b0 f  E DWORD  OutData;
$ I5 C4 x/ t2 w. [" m) J long  OutStream;
* A3 B0 b5 t/ f* A& i+ r CFile  BitmapFile; CFileException e;
double  SkipFloat = 0;
DWORD  ByteSkip = 0;
, Y6 q" ?2 S$ E) i- h, B( W0 e _ULARGE_INTEGER RealData;
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CreateILockBytesOnHGlobal(NULL, TRUE, &Buffer); // Create ILockBytes Buffer

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HRESULT hr = ::StgCreateDocfileOnILockBytes(Buffer,
. @7 H' w$ ^# C9 ]. e     STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, &pStorage);
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6 g  s" f7 ]' `. d1 N hr = pStorage->CreateStream(LPICTURE,
  STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, 0, &FileStream);
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8 U5 j; g+ K, `  M$ y! {+ W5 J m_pPict->SaveAsFile(FileStream, TRUE, &OutStream); // Copy Data Stream
9 k; v- C/ h1 Z FileStream->Release();
( C2 S" c3 ^  L8 t' b pStorage->Release();
Buffer->Flush();
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. u; W# Y: c( z2 b // Get Statistics For Final Size Of Byte Array
Buffer->Stat(&BytesStatistics, STATFLAG_NONAME);

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& m( ^' p6 y$ b$ X; s) s2 m* j // Cut UnNeeded Data Coming From SaveAsFile() (Leave Only Pure Picture Data)
0 W" i0 F' c: S. X  t SkipFloat = (double(OutStream) / 512); // Must Be In a 512 Blocks...
if(SkipFloat > DWORD(SkipFloat)) ByteSkip = (DWORD)SkipFloat + 1;
2 B* R* m: \4 R: Y! _ else ByteSkip = (DWORD)SkipFloat;
& E0 q* i( {0 {8 @$ ^. f ByteSkip = ByteSkip * 512; // Must Be In a 512 Blocks...
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( z  N' o- v0 h' R% o( V1 M // Find Difference Between The Two Values
1 H- J" j. `0 }2 ~ ByteSkip = (DWORD)(BytesStatistics.cbSize.QuadPart - ByteSkip);
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// Allocate Only The Pure Picture Data
; n. h4 o2 H# B8 R RealData.LowPart = 0;
4 a5 _' {. ^0 t; q: ] RealData.HighPart = 0;
3 k& P4 L- _* S# O! \+ c3 l& E" z! a RealData.QuadPart = ByteSkip;
BufferBytes = (BYTE*)malloc(OutStream);
if(BufferBytes == NULL)
* {9 D# A1 s* @  {
  Buffer->Release();
2 I3 M, d* ]9 j7 j  P  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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, k; k: ^* B  f8 _  V5 [* M. f/ k if(BitmapFile.Open(sFilePathName, CFile::typeBinary | CFile::modeCreate | CFile::modeWrite, &e))
  {
  BitmapFile.Write(BufferBytes, OutData);
" m/ @5 R- ^" W/ A  BitmapFile.Close();
# f3 N$ u9 B6 {2 w8 f8 I  bResult = TRUE;
1 K0 @4 s2 _, O% r5 `  }
else // Write File Failed...
  {
. l/ N7 d' K$ ]9 P  TCHAR szCause[255];
+ ^1 w8 V1 S0 }  e.GetErrorMessage(szCause, 255, NULL);
  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
! C$ |- f' v6 o  MessageBoxEx(hWnd, szCause, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
3 r+ S: e! J3 d8 {  bResult = FALSE;
  }

; G: {4 H& x- Q, i6 ?9 h9 b Buffer->Release();
' q4 O* S& `( ^ free(BufferBytes);
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return(bResult);
}