[收藏]IPicture::SaveAsFile的一个使用例子

天云上人

  BOOL CPicture::SaveAsBitmap(CString sFilePathName)
//=============================================================================
{
7 Z" {6 a! O7 P! `! o8 D BOOL bResult = FALSE;
, D( J, p" n! i- z% s0 N ILockBytes *Buffer = 0;
IStorage   *pStorage = 0;
IStream    *FileStream = 0;
  M& t. e% T: W+ ?* w# w( O- t BYTE    *BufferBytes;
2 ~/ y# z1 Z- Y$ f( g STATSTG  BytesStatistics;
% j+ N. X9 e3 e+ ^( o DWORD  OutData;
' @3 |; }) r. f1 o long  OutStream;
CFile  BitmapFile; CFileException e;
; X+ B$ g2 ~, X& w double  SkipFloat = 0;
DWORD  ByteSkip = 0;
_ULARGE_INTEGER RealData;



CreateILockBytesOnHGlobal(NULL, TRUE, &Buffer); // Create ILockBytes Buffer

7 p$ [' ~+ R9 ^7 f/ ]  ^3 \

& x' u% A# m" j7 F% L$ f+ W: s HRESULT hr = ::StgCreateDocfileOnILockBytes(Buffer,
) j% Z% N, [8 g; Z2 k     STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, &pStorage);
* U3 r, E% u; f6 Q  q

2 C" i% c- m% C" `& h
& a, j1 L# S+ E6 E" J1 V% _; W hr = pStorage->CreateStream(LPICTURE,
  STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, 0, &FileStream);



m_pPict->SaveAsFile(FileStream, TRUE, &OutStream); // Copy Data Stream
% m" R; z' c+ m0 y& u# s FileStream->Release();
pStorage->Release();
Buffer->Flush();
- \4 q" }9 q) \( \" d


- `3 _' F) E9 J( H // Get Statistics For Final Size Of Byte Array
Buffer->Stat(&BytesStatistics, STATFLAG_NONAME);


% E. d  ~; F% o
+ @! t! {/ }& u // Cut UnNeeded Data Coming From SaveAsFile() (Leave Only Pure Picture Data)
0 I0 ]/ U6 B! Q" E' ]; o' J SkipFloat = (double(OutStream) / 512); // Must Be In a 512 Blocks...
- Y1 Z4 B: _. _ if(SkipFloat > DWORD(SkipFloat)) ByteSkip = (DWORD)SkipFloat + 1;
1 W# a8 _! ^7 _- q3 j+ l* w else ByteSkip = (DWORD)SkipFloat;
ByteSkip = ByteSkip * 512; // Must Be In a 512 Blocks...
0 u( r  N8 \" p8 Z
& u: r& Y, l( u0 X5 p // Find Difference Between The Two Values
ByteSkip = (DWORD)(BytesStatistics.cbSize.QuadPart - ByteSkip);

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) ^4 U2 f! I0 W: e
// Allocate Only The Pure Picture Data
% W7 q, o) |, }6 u/ F# `2 p RealData.LowPart = 0;
RealData.HighPart = 0;
& p- p" C4 ]0 g! e  a, B8 [& ] RealData.QuadPart = ByteSkip;
. l% `: F7 f$ ^  j; L BufferBytes = (BYTE*)malloc(OutStream);
if(BufferBytes == NULL)
  {
  Buffer->Release();
& ]" ^5 f: v$ u4 [  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
  MessageBoxEx(hWnd, Can not allocate enough memory\\t, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
  }



Buffer->ReadAt(RealData, BufferBytes, OutStream, &OutData);
' H4 U" Y7 u! C( n* @
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' I+ Q: y+ l& a8 c if(BitmapFile.Open(sFilePathName, CFile::typeBinary | CFile::modeCreate | CFile::modeWrite, &e))
  {
  BitmapFile.Write(BufferBytes, OutData);
( X& L6 v- ?8 S1 @4 c" `  BitmapFile.Close();
  bResult = TRUE;
% Y0 a/ r9 c- k5 {" r& k  }
5 U* G) e3 i2 [- I. k else // Write File Failed...
  {
  TCHAR szCause[255];
+ h  x- L5 \& x3 h' C# s; m$ b) ]  e.GetErrorMessage(szCause, 255, NULL);
  HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
  MessageBoxEx(hWnd, szCause, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
  bResult = FALSE;
  }
, L( V3 n2 I+ v# [3 d  J8 j% d; n
# v. ]& T" ^4 D  ^2 y% u/ M Buffer->Release();
/ O: W# _9 ]' H  [ free(BufferBytes);


& a, t  l  f5 X+ m7 z& c. A
3 B* O2 ~7 ~0 S% |+ Q, M- Y6 q return(bResult);
}