含有虚继承的多继承构造函数执行顺序

 1 #include<iostream>
 2 using namespace std;
 3 
 4 class Base1
 5 {
 6 public:
 7     Base1()
 8     {
 9         cout << "class Base1" << endl;
10     }
11 };
12 
13 class Base2 
14 {
15 public:
16     Base2()
17     {
18         cout << "class Base2" << endl;
19     }
20 };
21 
22 class Level1:public Base2,virtual public Base1
23 {
24 public:
25     Level1()
26     {
27         cout << "class Level1" << endl;
28     }
29 };
30 
31 class Level2:public Base2,virtual public Base1
32 {
33 public:
34     Level2()
35     {
36         cout << "class Level2" << endl;
37     }
38 };
39 
40 class TopLevel:public Level1,virtual public Level2 
41 {
42 public:
43     TopLevel()
44     {
45         cout << "class TopLevel" << endl;
46     }
47 };
48 
49 int main()
50 {
51     TopLevel obj;   
52 }

执行结果 

class Base1
class Base2
class Level2
class Base2
class Level1
class TopLevel

结论：
虚基类的构造函数优先执行