C++ 基类,子对象,派生类构造函数调用顺序

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#include <iostream>
using namespace std;class A {public:A( )  {cout << "A Constructor………" << endl;}~A( )  {cout << "A Destructor………" << endl;}
};class B: public A {public:B( )  {cout << "B Constructor………" << endl;}~B( )  {cout << "B Destructor………" << endl;}
};int  main() {B   b;return 0;
}

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#include <iostream>
using namespace std;class A {public:A( )  {cout << "A Constructor………" << endl;}~A( )  {cout << "A Destructor………" << endl;}
};class B {public:B( )  {cout << "B Constructor………" << endl;}~B( )  {cout << "B Destructor………" << endl;}
};class C: public A, B { //构造函数调用顺序，先A后B，和书写(继承)顺序相同public:C( )  {cout << "C Constructor………" << endl;}~C( )  {cout << "C Destructor………" << endl;}
};int main() {C   c;return 0;
}

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#include <iostream>
using namespace std;class B1 {public:B1() {cout << "constructing B1 " << endl;}
};class B2 {public:B2() {cout << "constructing B2 " << endl;}
};class B3 {public:B3() {cout << "constructing B3 " << endl;}
};class C {public:C(): memberB1(), memberB2(), memberB3() {     }private://构造函数的调用顺序和对象的创建先后顺序有关B2 memberB2;B1 memberB1;B3 memberB3;
};int  main() {C obj;          //  B2  B1  B3return 0;
}

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#include <iostream>
using namespace std;class A {public:A()  {cout << "A Constructor………" << endl;}~A()  {cout << "A Destructor………" << endl;}
};class B {public:B()  {cout << "B Constructor………" << endl;}~B()  {cout << "B Destructor………" << endl;}
};class C: public A {private:B obj_b;public:C()  {cout << "C Constructor………" << endl;}~C()  {cout << "C Destructor………" << endl;}
};int  main() {C   obj;return 0;
}