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:
#include <iostream>
class 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。