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how can i set a file locked?

Posted on 2002-06-25
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Last Modified: 2013-11-20
when i open a file in my program, i could delete the file when it opened.I want to lock it. what can I do?
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Question by:quace
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5 Comments
 
LVL 32

Expert Comment

by:jhance
ID: 7107013
With MFC's CFile class you lock a file with the constructor or the Open member function:

CFile x(lpszFilename, CFile::modeWrite | CFile::shareExclusive);

the CFile::shareExclusive flag locks the file for EXCLUSIVE access to this opening.
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Author Comment

by:quace
ID: 7109473
Could you tell me how to do in mfc framework?
I use CDocument::OnOpenDocument()
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LVL 32

Expert Comment

by:jhance
ID: 7110137
Believe it or not, CFile _IS_INDEED_ an MFC class.

Beyond that, I'm really don't know what you mean by "do in mfc framework", please explain.
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Author Comment

by:quace
ID: 7112504
doc/view architecture
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LVL 1

Accepted Solution

by:
jianliuer earned 60 total points
ID: 7116174
hi,quace


pls step into BOOL CDocument::OnOpenDocument(...)

and u can find following lines:

....
          CWaitCursor wait;
          if (pFile->GetLength() != 0)
               Serialize(loadArchive);     // load me
          loadArchive.Close();
          ReleaseFile(pFile, FALSE);

....


the file will be closed after u call the default implement CDocument::OnOpentDocument(...).So u can try this:


CYOURDocument::OnOpenDocument(...)
{
if(m_pFile != NULL)
{
 ReleaseFile(pFile, FALSE);
}
 CDocument::OnOpenDocument(...);
 m_pFile = GetFile(lpszPathName,
 CFile::modeRead|CFile::shareDenyWrite, &fe);
 if (m_pFile == NULL)
     {
          ReportSaveLoadException(lpszPathName, &fe,
               FALSE, AFX_IDP_FAILED_TO_OPEN_DOC);
          return FALSE;
     }
 ....
}

CYOURDocument::CYOURDocument()
{
m_pFile = NULL;
}

CYOURDocument::~CYOURDocument()
{
if(m_pFile != NULL)
{
 ReleaseFile(pFile, FALSE);
}
}

where m_pFile is a class member of CYOURDocument CFile* m_pFile.

GOOD LUCK!
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