What is the method for invoking a virtual method of a derived class from the constructor of the base class?

edit

It is generally not recommended to invoke a virtual method of a derived class from the constructor of the base class because the object may not be fully initialized yet. However, if it is necessary to do so, the following approach can be used:

1. Declare the virtual method in the base class and implement it in the derived class.
2. Call the virtual method in the constructor of the base class, using the syntax this->virtual_method() or Base::virtual_method().
3. Ensure that any code in the virtual method does not rely on uninitialized members or behavior.

Example:

class Base {
public:
    Base() {
        this->initialize(); // Calls virtual method defined in derived class
    }

    virtual void initialize() {
         // This method will be overridden in the derived class
    }
};

class Derived : public Base {
public:
    Derived() {}

    void initialize() override {
         // Code to initialize the derived class
    }
};