I met trouble in using CFile class
if i uncomment  " nFile.Close(); "
I met trouble
why?
help me!

// Example

const int m_nLength = 100;
float m_fData[m_nLength];
for(int i=0;i<m_nLength;i++)
   m_fData[i] = (float)sin(2*3.1415*i/m_nLength);

CFile outFile;
CFileException e;
if( !outFile.Open("c:\\test_bin.txt",
    CFile::modeCreate| File::modeWrite, &e) )
  {
#ifdef _DEBUG
   afxDump << "File could not be opened " << e.m_cause << "\n";
#endif  return;
  }
  outFile.Write((char*)m_fData,sizeof(float)*m_nLength);
  outFile.Close();

  for(i=0;i<m_nLength;i++) m_fData[i] = 0.f;

  CFile inFile;
  CFileException ee;
  if( !inFile.Open("c:\\test_bin.txt",CFile::modeRead, &ee) )
  {
#ifdef _DEBUG
   afxDump << "File could not be opened " << ee.m_cause << "\n";
#endif  return;
  }
  inFile.Read((char*)m_fData,sizeof(float)*m_nLength);

************************************
//   nFile.Close();
************************************

Check to make sure Read() isn't throwing an exception for some reason.
Otherwise, no idea. :-)