CByteArrayFile -- A class used to serialize object with database field

In this example, I will show you a class named CByteArrayFile. It is a derive class of CMemFile. With this class, we can serialize object into CByteArray object. And then, we can use DFX_Binary to transfter data into database "long binary" field.

Follwing is the sample code of how to use the CByteArrayFile class.

In the class which need to be serialize, such as CSomeClass.cpp

/////////////////////////////////////////////////////////////////////////////////////////////
CSomeClass::TransDataWithByteArray(CByteArray& byteArray, BOOL bStore)
{
 CByteArrayFile byFile;
 byFile.SetArray(&byteArray);    // attach byteArray with byFile
 if (bStore) // store object into byteArray
 {
  CArchive ar( &byFile, CArchive::store); // create CArchive object with CByteArray File
  Serialize(ar);    // Call CSomeClass::Serialize function
  ar.Close();
 }
 else // load object from byteArray
 {
  CArchive ar( &byFile, CArchive::load);
  Serialize(ar);    // Call CSomeClass::Serialize function
  ar.Close();
 }
 
 // important!!, detach byteArray with byFile. Or byteArray will be free with byFile
 byFile.Detach();
}

/////////////////////////////////////////////////////////////////////////////////////////////
CSomeDaoRecordset rs;    // rs.m_byteLongField is a CByteArray class
CSomeClass object;
// 1. Write to record
rs.Open(. . .);
rs.AddNew();
object.TransDataWithByteArray(rs.m_byteLongField, TRUE /* store */);
. . .
rs.Update();
rs.Close();

// 2. Read from record
rs.Open(. . .);
object.TransDataWithByteArray(rs.m_byteLongField, FALSE /* load */);
...

rs.Close();

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Date Last Updated: April 3, 1999