C / C++ / MFC

Mark Salsbery wrote:

ReadObject() throws exceptions instead of returning a NULL pointer

Mark Salsbery wrote:

either write a count value to the archive and retrieve it
when deserializing,

Trupti Mehta wrote:

I didn't found which exceptions ReadObject throws.

Trupti Mehta wrote:

Can you guide me how to achieve the above

// Writing...

  CArchive ar(&myfile, CArchive::store);   

  ar << (int)opdtMap.GetCount();  

  for (POSITION pos = opdtMap.GetStartPosition(); pos != NULL; )  
  {   
   opdtMap.GetNextAssoc(pos, key, od );    
   ar << &od;   
  }   


// Reading...

  CArchive ar(&myfile, CArchive::load);   
  
  int count;
  ar >> count;
  
  for (int i = 0; i < count; i++) 
  {   
   ar >> od; 
   ...

Mark Salsbery
Microsoft MVP - Visual C++

newOperMap.SetAt(1, OperatorDetails(1, _T("One")));
newOperMap.SetAt(2, OperatorDetails(2, _T("Two")));
db.WriteOperators(newOperMap);

		for (POSITION pos = opdtMap.GetStartPosition(); pos != NULL;) {
			int key;
			OperatorDetails od;
			opdtMap.GetNextAssoc(pos, key, od ); 
//			ar.WriteObject(&od);
			ar << &od;
		}

   ÿÿ
  OperatorDetails   Two 

    OperatorDetails* od;

for (int i=0; i < count; i++) {
    OperatorDetails odObj;
    ar >> od;
    if (od == NULL)
        break;

    odObj.SetOperatorNo(od->GetOperatorNo());
    odObj.SetOperName(od->GetOperName());
    operMap->SetAt(odObj.GetOperatorNo(), odObj);
}
    delete od;

CMap<int, int&, OperatorDetails, OperatorDetails&>

Mark Salsbery
Microsoft MVP - Visual C++

// Serialize
void OperatorDetails::Serialize(CArchive &ar)
{
	if (ar.IsStoring())
		ar << operNo << operName;
	else
		ar >> operNo >> operName;

}

Trupti Mehta wrote:

for (POSITION pos = opdtMap.GetStartPosition(); pos != NULL [Wink] {
int key;
OperatorDetails od;
opdtMap.GetNextAssoc(pos, key, od );
// ar.WriteObject(&od);
ar << &od;
}

typedef CMap<int, int, OperatorDetails, OperatorDetails&> OperatorDetailsMap;

template <> void AFXAPI SerializeElements <OperatorDetails> (CArchive &ar, OperatorDetails *pOperatorDetails, INT_PTR nCount)
{
	for (int i = 0; i < nCount; i++, pOperatorDetails++)
	{
		pOperatorDetails->Serialize(ar);
	}
}

void WriteArchive()
{
	OperatorDetailsMap newOperMap;   
	newOperMap.SetAt(1, OperatorDetails(1, _T("One")));   
	newOperMap.SetAt(2, OperatorDetails(2, _T("Two")));   

	CFile myfile(_T("e:\\archive_test.txt"), CFile::modeCreate | CFile::modeWrite | CFile::shareDenyWrite);
	CArchive ar(&myfile, CArchive::store);   

	newOperMap.Serialize(ar);

	ar.Close();
	myfile.Close();
}

void ReadArchive()
{
	OperatorDetailsMap newOperMap;

	CFile myfile(_T("e:\\archive_test.txt"), CFile::modeRead | CFile::shareDenyNone);
	CArchive ar(&myfile, CArchive::load);   

	newOperMap.Serialize(ar);

	ar.Close();
	myfile.Close();
}

Mark Salsbery
Microsoft MVP - Visual C++

Linking...
MC_AppView.obj : error LNK2005: "void __cdecl SerializeElements(class CArchive &,class OperatorDetails *,int)" (?SerializeElements@@YAXAAVCArchive@@PAVOperatorDetails@@H@Z) already defined in DbOperations.obj
Operator.obj : error LNK2005: "void __cdecl SerializeElements(class CArchive &,class OperatorDetails *,int)" (?SerializeElements@@YAXAAVCArchive@@PAVOperatorDetails@@H@Z) already defined in DbOperations.obj
ARMV4IDbg/MC_App.exe : fatal error LNK1169: one or more multiply defined symbols found
Error executing link.exe.

Trupti Mehta wrote:

I removed the template <> SerializeElements() from the code & ran the application. Its still running and giving the results as we expected,

Mark Salsbery
Microsoft MVP - Visual C++

typedef CMap<int, int, OperatorDetails, OperatorDetails&> OperatorDetailsMap;
typedef CMap<int, int, DeptDetails, DeptDetails&> DeptDetailsMap;

class ....{
	// MAPS
	OperatorDetailsMap* operMap;
	DeptDetailsMap deptMap;

In .cpp
// Copy Constructor
DbOperations::DbOperations(const DbOperations &d) {
	this->operMap = d.operMap;
//	this->deptMap = d.deptMap;
}
// = Assignment operator
DbOperations& DbOperations::operator=(const DbOperations &d) {
	this->operMap = d.operMap;
//	this->deptMap = d.deptMap;

	return *this;
}
/*template <> void AFXAPI SerializeElements <OperatorDetails> (CArchive &ar, OperatorDetails *pOperatorDetails, INT_PTR nCount){
	for (int i = 0; i < nCount; i++, pOperatorDetails++)	{
		pOperatorDetails->Serialize(ar);
	}
}*/

huke1987 wrote:

SOS

Naveen wrote:

I said to do so for debugging..