destructor Destroy; virtual;
__fastcall virtual ~TObject();
Disposes of an object instance.
When declaring a Destroy method in a descendant, always add the override directive to the declaration and call the inherited Destroy as the last statement in the overriding method. Because Destroy is a virtual method, overriding it ensures that the proper inherited behavior occurs.
Destroy should be implemented so that it calls Free on all subobjects created within the object's constructor (that is, allocated by the constructor). Unlike Destroy, Free provides a safeguard when destroying objects that are nil.