继承

1、单继承

class Base{public:                Base()                {                                cout << "Base()" << this << endl;                }                 void FunTest1()                {                                cout << "Base::FunTest1()" << endl;                }                 void FunTest2()                {                                cout << "Base::FunTest2()" << endl;                }                ~Base()                {                                cout << "~Base()" << endl;                }                 int _data1;};class Derive :public Base{public:                 void FunTest3()                {                                cout << "Derive::FunTest3()" << endl;                }                 int _data2;};int main(){                 Base b;                b.FunTest1();                b.FunTest2();                b._data1 = 0x04;                 Derive d;                d.FunTest1();                d.FunTest2();                d.FunTest3();                d._data1 = 0x01;                d._data2 = 0x02;                 return 0;}

——b对象和d对象的对象模型

main 函数的反汇编

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派生类的构造函数:

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程序运行结果:

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构造函数:

基类构造函数:Base( )884 ->派生类构造函数: Base( )874 ->Derive( )874

析构函数:

派生类的析构函数:~Derive( )874 -> ~Base( )874->基类的析构函数:~Base( )884

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2、多继承

class Base{public:                Base()                {                                cout << "Base()" << this << endl;                }                 void FunTest1()                {                                cout << "Base::FunTest1()" << endl;                }                 void FunTest2()                {                                cout << "Base::FunTest2()" << endl;                }                ~Base()                {                                cout << "~Base()" << endl;                }                 int _data1;};class Base1{public:                Base1()                {                                cout << "Base1()" << endl;                }                 void FunTest3()                {                                cout << "Base::FunTest3()" << endl;                }                 void FunTest4()                {                                cout << "Base::FunTest4()" << endl;                }                 int _data3;};class Derive :public Base,public Base1{public:                Derive()                {                                cout << "Derive()" << this << endl;                }                 void FunTest5()                {                                cout << "Derive:FunTest5()" << endl;                }                ~Derive()                {                                cout << "~Derive()" << endl;                }                 int _data2;};int main(){                 Base b;                b.FunTest1();                b.FunTest2();                b._data1 = 0x04;                 Base1 b1;                b1.FunTest3();                b1.FunTest4();                b1._data3 = 0x05;                 Derive d;                d.FunTest1();                d.FunTest2();                d.FunTest3();                d.FunTest4();                d.FunTest5();                d._data1 = 0x01;                d._data2 = 0x02;                d._data3 = 0x03;                 return 0;}

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main函数的反汇编:

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派生类的构造函数:

先调用Base的构造函数,再调用Base1的构造函数

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析构函数的调用:

先是派生类的析构函数,再试Base1的析构函数,最后是Base的析构函数

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在派生类的析构函数中又会调用基类的析构函数:

在派生类的析构函数中,也是先调用Base1的析构函数,再调用Base的析构函数。与构造函数的顺序正好相反

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程序运行的结果:

构造函数:

j基类的构造函数:Base( )D9c -> Base1( )D90 -> 派生类中的构造函数:Base( )D7c ->  Base1 ( )D80 -> Derive( )D7c 

析构函数:

派生类中的析构函数:~Derive( )D7c -> ~Base1( )D80 -> ~Base( )D7c  ->基类的析构函数:~Base1( )D90 -> ~Base( )D9C 

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3、菱形继承

class Base{public :                Base()                {                                cout << "Base()" << this << endl;                }                 void FunTest1()                {                                cout << "Base::FunTest1()" << endl;                }                ~Base()                {                                cout << "~Base()" << endl;                }};class Derive : public Base{public :                Derive()                {                                cout << "Derive()" << this << endl;                }                 void FunTest2()                {                                cout << "Derive:FunTest2()" << endl;                }                ~Derive()                {                                cout << "~Derive()" << endl;                }};class Derive1 : public Base{public :                Derive1()                {                                cout << "Derive1()" << this << endl;                }                 void FunTest3()                {                                cout << "Derive:FunTest4()" << endl;                }                ~Derive1()                {                                cout << "~Derive1()" << endl;                }};class Derive2 : public Derive ,public Derive1{public :                Derive2()                {                                cout << "Derive2()" << endl;                }                 void FunTest4()                {                                cout << "Derive:FunTest4()" << endl;                }};int main(){                 Base b;                b.FunTest1();                 Derive d;                d.FunTest1();                d.FunTest2();                 Derive1 d1;                d1.FunTest1();                d1.FunTest3();                 Derive2 d2;                 //d2.FunTest1();会出现二义性                d2. Derive ::FunTest1();                d2. Derive1 ::FunTest1();                d2.FunTest2();                d2.FunTest3();                d2.FunTest4();                 return 0;}

对象模型:

Derive和Derive1中都含有了Base,会产生二义性和数据冗余。

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main函数的反汇编:

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派生类的构造函数:

在派生类的构造函数中,都先调用的基类的构造函数。

Derive()

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Derive1()

Derive2()

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析构函数的调用:

析构函数的顺序和构造函数的顺序正好相反。

~Derive2( )->~Derive1( )->~Derive( )->~Base( ),

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派生类中析构函数的调用:

在~Derive2(),先是自己的析构函数,再调用了~Derive1(),再调用了~Derive(),

在~Derive1( )中先是自己的析构函数,又调用了~Base()

在~Derive( )中先是自己的析构函数,又调用了~Base()

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程序运行结果:

构造函数:

Base( )B8F   ->

Derive的构造函数:Base( )B83 -> Derive( )B83->

Derive1的构造函数:Base( )B77 -> Derive1( )B77->

Derive2的构造函数:Base( )B6B -> Derive( )B6B     ->Base( )B6C -> Derive1( )B6C         ->Derive2( )B6B

析构函数:

~Derive2( )B6B -> ~Derive1( )B6C ->~Base( )B6C -> ~Derive( )B6B -> ~Base( )B6B 

~Derive1( )B77 -> ~Base( )B77 -> ~Derive( )B83 -> ~Base( )B83 

~Base( )B8F

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