c++ 类成员的初始化顺序

Posted 2022-12-26 xiaoxiaoshuai-

 1 class TestClass1
 2 
 3 public:
 4     TestClass1()
 5     
 6         cout << "TestClass1()" << endl;
 7     
 8     TestClass1(const TestClass1&)
 9     
10         cout << "TestClass1(const TestClass1&)" << endl;
11     
12     TestClass1(int i)
13     
14         cout << "TestClass1(int i) " << i << " " <<endl;
15     
16 ;
17 
18 class TestClass2
19 
20 public:
21     TestClass2()  cout << "TestClass2()" << endl; 
22     TestClass2(const TestClass2&) cout << "TestClass2(const TestClass2&)" << endl; 
23     int fun()  return 2; 
24 ;
25 
26 class TestClass3
27 
28 public:
29     TestClass3(TestClass2& tc2):m_tc2(tc2),m_tc1(m_tc2.fun()) ;
30 private:
31     TestClass1 m_tc1;
32     TestClass2 m_tc2;
33 ;
34 
35 int main()
36 
37     TestClass2 tc2;
38     cout << "................................................\\n";
39     TestClass3 tc3(tc2);
40     return 0;
41 

 

结果：

 

 

明明TestClass1的初始化依赖TestClass2，为何TestClass1先于TestClass2初始化。