C++用纯虚析构函数定义一个抽象类

// deriv_RestrictionsOnUsingAbstractClasses.cpp
// Declare an abstract base class with a pure virtual destructor.
// It's the simplest possible abstract class.
class base
{
public:
    base() {}
    // To define the virtual destructor outside the class:
    virtual ~base() = 0;
    // Microsoft-specific extension to define it inline:
//  virtual ~base() = 0 {};
};

base::~base() {} // required if not using Microsoft extension

class derived : public base
{
public:
    derived() {}
    ~derived() {}
};

int main()
{
    derived aDerived; // destructor called when it goes out of scope
}

参考链接：

抽象类 (C++) | Microsoft Learn