是的,C++析构函数支持虚析构。在C++中,当一个类被设计为基类时,并且这个类有虚函数,那么它的析构函数也应该是虚的。这是为了确保当通过一个基类指针删除一个派生类对象时,能够正确地调用派生类的析构函数,从而避免资源泄漏。
以下是一个包含虚析构函数的基类示例:
#includeclass Base { public: Base() { std::cout << "Base constructor called" << std::endl; } virtual ~Base() { std::cout << "Base destructor called" << std::endl; } virtual void foo() { std::cout << "Base foo function called" << std::endl; } }; class Derived : public Base { public: Derived() { std::cout << "Derived constructor called" << std::endl; } ~Derived() { std::cout << "Derived destructor called" << std::endl; } void foo() override { std::cout << "Derived foo function called" << std::endl; } }; int main() { Base* ptr = new Derived(); ptr->foo(); delete ptr; // 调用的是派生类的析构函数,然后是基类的析构函数 return 0; }
输出结果:
Base constructor called Derived constructor called Derived foo function called Base destructor called Derived destructor called
在这个例子中,基类Base
有一个虚析构函数,派生类Derived
继承自Base
并重写了foo()
函数。在main()
函数中,我们通过基类指针ptr
删除派生类对象,这时会先调用派生类的析构函数,然后调用基类的析构函数。