1、调用基类构造函数,调用顺序按照他们被继承时声明的顺序(从左到右)
2、调用成员对象的构造函数,调用顺序按照它们在类中声明的顺序
3、最后调用本类的构造函数
#include <iostream> using namespace std; class B1 //基类B1,构造函数有参数 {public: B1(int i) {cout<<"constructing B1 "<<i<<endl;} }; class B2 //基类B2,构造函数有参数 {public: B2(int j) {cout<<"constructing B2 "<<j<<endl;} }; class B3 //基类B3,构造函数无参数 {public: B3(){cout<<"constructing B3 *"<<endl;} }; class C: public B2, public B1, public B3 { public: //派生类的公有成员 C(int a, int b, int c, int d): B1(a),memberB2(d),memberB1(c),B2(b)
{
cout<<"constructing c *"<<endl;
} private: //派生类的私有对象成员 B1 memberB1; B2 memberB2; B3 memberB3; }; int main() { C obj(1,2,3,4); }
结果:
constructing B2 2 constructing B1 1 constructing B3 * constructing B1 3 constructing B2 4 constructing B3 * constructing c *