C / C++ / MFC

CBaseClass {
     <font style="color:blue;">int</font> m_iField;
 <font style="color:blue;">public</font>:
     CBaseClass();
     ~CBaseClass();
     CBaseClass <font style="color:blue;">operator</font>=(CBaseClass& ref);
};
CSubClass : CBaseClass {
 <font style="color:blue;">public</font>:
     CSubClass();
     ~CSubClass();
     CSubClass& <font style="color:blue;">operator</font>=(CSubClass& ref);
};

<font style="color:blue;">void</font> main (<font style="color:blue;">void</font>) {
     CSubClass  CSObj1, CSObj2;
     CBaseClass& refCBObj = CSObj1; <font style="color:green;">// Allowed because CSubClass is derived from CBaseClass</font>

     refCBOb2 = CSObj2; <font style="color:green;">// CBaseClass::Operator=()
}</font>

CBaseClass {
 <font style="color:blue;">public</font>:
     CBaseClass();
     <font style="color:blue;">virtual</font> ~CBaseClass(); <font style="color:green;">// Will call The SubClass Destructor</font>
     CBaseClass <font style="color:blue;">operator</font>=(CBaseClass& ref);
};

class CPerson{
  CPerson& operator =(const CPerson& other);
}
class ATypeOfPerson : public CPerson{
  ATypeOfPerson & operator =(const ATypeOfPerson & other);
}
ATypeOfPerson & ATypeOfPerson ::operator=(const ATypeOfPerson & other)
{
  CPerson::operator=( other );
  return *this;
}

ATypeOfPerson& ATypeOfPerson::operator=(const ATypeOfPerson& other) {
   if(this != &other) {
      CPerson::operator=(other);
      // Then ATypeOfPerson specific code
   }
   return *this;
}