FIX: CDaoTableDef CreateField Cannot Set "Allow Zero Length"

RESOLUTION

1. Copy the code for AfxSetFieldInfo() from Daocore.cpp into your project as a separate function. Then modify the line containing the bug. Remove the exclamation mark (!) in the first line, and change AFX_DAO_FALSE to AFX_DAO_TRUE in the second line:

      void MyCreateField()
      {
      CDaoDatabase db;
      db.Open("c:\\msdev\\projects\\daoenrol\\stdreg32.mdb",
         FALSE, FALSE);
   
      // create a tabledef
      CDaoTableDef td ( &db );
      td.Create(_T("Table1"),0,_T("Table1"), NULL);
   
      // create a FieldInfo structure
      struct CDaoFieldInfo m_FI;
   
      m_FI.m_nOrdinalPosition = 0;
   
      // always initialize the rest
      m_FI.m_strName = _T("MyField");
      m_FI.m_nType = dbText ;
      m_FI.m_lSize = 20;
      m_FI.m_bAllowZeroLength = TRUE;  // To set "Allow Zero Length"
   
      m_FI.m_strDefaultValue = _T("");
      m_FI.m_bRequired = FALSE;
      m_FI.m_lAttributes = dbUpdatableField;
   
      m_FI.m_strValidationRule = _T("");
      m_FI.m_strValidationText = _T("");
   
      // Copy code from CDaoTableDef::CreateField()
   
      DAOField* pDAOField;
   
      // Create the DAO field object (setting basic properties)
   
      // DAO_CHECK(m_pDAOTableDef->CreateField(
      DAO_CHECK(td.m_pDAOTableDef->CreateField(
         COleVariant(m_FI.m_strName, VT_BSTRT),
         COleVariant(m_FI.m_nType),
         COleVariant(m_FI.m_lSize), &pDAOField));
   
      TRY
      {
      // Basic properties already set, so set the rest
      MyAfxSetFieldInfo(pDAOField, m_FI);
   
      // Append the field object to the fields collection
      if (td.m_pDAOFields == NULL)
          // cannot call private member function
          //td.InitFieldsCollection();
          DAO_CHECK(td.m_pDAOTableDef->get_Fields (&(td.m_pDAOFields)));
   
      DAO_CHECK(td.m_pDAOFields->Append(pDAOField));
      }
      CATCH_ALL(e)
      {
         pDAOField->Release();
         THROW_LAST();
      }
      END_CATCH_ALL
   
      pDAOField->Release();
   
      td.Append();
      }