#include <fstream>
using namespace std;
ofstream out("order.out");
#define CLASS(ID) class ID { \
public: \
ID(int) { out << #ID " constructor\n"; } \
~ID() { out << #ID " destructor\n"; } \
};
CLASS(Base1);
CLASS(Member1);
CLASS(Member2);
CLASS(Member3);
CLASS(Member4);
class Derived1 : public Base1 {
Member1 m1;
Member2 m2;
public:
Derived1(int) : m2(1), m1(2), Base1(3) {
out << "Derived1 constructor\n";
}
~Derived1() {
out << "Derived1 destructor\n";
}
};
class Derived2 : public Derived1 {
Member3 m3;
Member4 m4;
public:
Derived2() : m3(1), Derived1(2), m4(3) {
out << "Derived2 constructor\n";
}
~Derived2() {
out << "Derived2 destructor\n";
}
};
int main() {
Derived2 d2;
}
“请注意,构造函数不是默认构造函数;它们每个都有一个 int 参数。参数本身没有标识符;它存在的唯一原因是强制您显式调用初始化列表中的构造函数”