Write file of base objects into vector of derived objects

[cbpetro]

I have a binary file that I have written base objects. I want to read those base objects into a vector of objects that I have derived from base.

Can it be done and how.

#include <vector>

class CBase
{
public:
	CBase( ) : m_val1(0.0f),
			   m_val2(0.0f) { }

	virtual ~CBase( ) { }

	float	m_val1;
	float	m_val2;
};

class CDerived : public CBase
{
public:
	CDerived( ) : m_val3(0.0f) { }
	CDerived(const CBase& base ) : CBase(base),
		                           m_val3(0.0f) { }

	virtual ~CDerived( ) { }

	float	m_val3;
};

int main(int argc, char* argv[])
{
	// how to: read base objects into vector of derived objects
	std::vector<CDerived> myVector;
	myVector.resize(5);

	// let's say my binary file has 5 base objects in it
	FILE *fp = fopen("somefile", "rb");
	// can I write this line of code to write the base objects into vector
	fread(&myVector[0], 5, sizeof(CBase), fp);
	fclose( fp );
	
	return 0;
}