Question

I want to Serialize a class that’s part of inheritance. I’m using C++98 and no 3rd party libraries. Here is my class structure:

class Base{
public:
    virtual RunMe()=0;
};

class Derived: public Base{
    virtual RunMe(){
        std::cout << "I am running << std::endl;
    }
};

I am able to Serialize a basic class using ofstream and fstream, via friend technique. But I can’t figure out how to implement Serialization in case where my Base class has a pure virtual function.

Answer 1

Add serialization support methods to your base class.
Your child classes would first call the base class support methods, then their own.

class Base
{
  public:
    virtual void binary_write(ostream& out) // Serialization support function.
    {
        out.write(&m_base_variable, sizeof(m_base_variable));
    }
  private:
    unsigned int m_base_variable;
};


class Derived
: public Base
{
  public:
    virtual void binary_write(ostream& out) // Serialization support function
    {
        Base::binary_write(out); // Call Base's method first;
        out.write(m_derived_variable, sizeof(m_derived_variable));
    }
  private:
    double m_derived_variable;
};