CONY的世界

Normally you will have to explicitly declare your own destructor if:

1.You are declaring a class which is supposed to serve as a base for inheritance involving polymorphism, if you do you'll need a virtual destructor to make sure that the destructor of a Derived class is called upon destroying it through a pointer/reference to Base.

2.You need to release resourced aquired by the class during its leftime

Example 1: The class has a handle to a file, this needs to be closed when the object destructs; the destructor is the perfect location.

Exempel 2: The class owns an object with dynamic-storage duration, since the lifetime of the object can potentially live on long after the class instance has been destroyed you'll need to explicitly destroy it in the destructor.