1.一个基类base,被类a虚继承,类a被其他的类继续继承,那么base中的初始化必须由派生类的最后一个完成,其中任意一个都不能代替完成基类,如果在最后一个派生类里不进行这个base的初始化,那么就会调用相应的无参构造,值是随机数,这个也适用于一条链中的任意一个
2.只要存在虚继承,那么虚继承就会首先被调用,存在多种虚继承,则是根据以下被调用的顺序
class son2 : public son3,public son1,public son4//顺序从这里来
#include<iostream>
using namespace std;
class base1
{
private:
int a, b;
public:
base1() { cout << "这儿是一个基类base1" << endl; show(); };
base1(int a, int b) :a(a), b(b) {
cout << "有参构造base1" << endl; show();
};
void show()
{
cout << a << " " << b << endl;
}
};
class base2
{
private:
int a, b;
public:
base2() { cout << "这儿是一个基类base2" << endl; show(); };
base2(int a, int b) :a(a), b(b) {
cout << "有参构造base2" << endl; show();
};
void show()
{
cout << a << " " << b << endl;
}
};
class son1 :virtual public base1
{
private:
int c;
public:
son1() { cout << "这是儿子一号" << endl; };
son1(int a, int b, int c) :base1(a, b), c(c) {
cout << "进行son1有参构造" << endl; show();
};
void show()
{
cout << c << endl;
base1::show();
}
};
class son3 :virtual public base2
{
private:
int c;
public:
son3() { cout << "这是儿子三号" << endl; };
son3(int a, int b, int c) :base2(a, b), c(c) {
cout << "进行son3有参构造" << endl; show();
};
void show()
{
cout << c << endl;
base2::show();
}
};
class son4 :public base2
{
private:
int c;
public:
son4() { cout << "这是儿子三号" << endl; };
son4(int a, int b, int c) :base2(a, b), c(c) {
cout << "进行son4有参构造" << endl; show();
};
void show()
{
cout << c << endl;
base2::show();
}
};
class son2 : public son3,public son1,public son4//顺序从这里来
{
private:
int c;
public:
son2() { cout << "这是儿子二号" << endl; };
son2(int a, int b, int c, int d, int e, int f, int g) :son3(d, e, f),son1(a,b,c),son4(d,e,f),c(g){
cout << "进行son2有参构造" << endl; show();
};
void show()
{
cout << c << endl;
son1::show();
son3::show();
son4::show();
}
};
class me : public son2
{
public:
me() { cout << "这是我" << endl; };
me(int a, int b, int c, int d, int e, int f, int g) : son2(a, b, c, d, e, f, g),base2(a,b),base1(a,b) {};
};
int main()
{
me i(1, 2, 3, 4, 5, 6, 7);
}
#include<iostream>
using namespace std;
class base1
{
private:
int a, b;
public:
base1() { cout << "这儿是一个基类base1" << endl; show(); };
base1(int a, int b) :a(a), b(b) {
cout << "有参构造base1" << endl; show();
};
void show()
{
cout << a << " " << b << endl;
}
};
class base2
{
private:
int a, b;
public:
base2() { cout << "这儿是一个基类base2" << endl; show(); };
base2(int a, int b) :a(a), b(b) {
cout << "有参构造base2" << endl; show();
};
void show()
{
cout << a << " " << b << endl;
}
};
class son1 : public base1
{
private:
int c;
public:
son1() { cout << "这是儿子一号" << endl; };
son1(int a, int b, int c) :base1(a, b), c(c) {
cout << "进行son1有参构造" << endl; show();
};
void show()
{
cout << c << endl;
base1::show();
}
};
class son3 :virtual public son1
{
private:
int c;
public:
son3() { cout << "这是儿子三号" << endl; };
son3(int a, int b, int c) :son1(a, b,c), c(c) {
cout << "进行son3有参构造" << endl; show();
};
void show()
{
cout << c << endl;
son1::show();
}
};
class son4 :public son3
{
private:
int c;
public:
son4() { cout << "这是儿子四号" << endl; };
son4(int a, int b, int c) :son3(a, b,c), c(c) {
cout << "进行son4有参构造" << endl; show();
};
void show()
{
cout << c << endl;
son3::show();
}
};
/*class son2 : public son1, public son3, public son4
{
private:
int c;
public:
son2() { cout << "这是儿子二号" << endl; };
son2(int a, int b, int c, int d, int e, int f, int g) :son3(d, e, f),son1(a,b,c),son4(d,e,f),base1(a,b),base2(a,b),c(g){
cout << "进行son2有参构造" << endl; show();
};
void show()
{
cout << c << endl;
son1::show();
son3::show();
son4::show();
}
};
class me : public son2
{
public:
me() { cout << "这是我" << endl; };
me(int a, int b, int c, int d, int e, int f, int g) : son2(a, b, c, d, e, f, g) {};
};*/
int main()
{
son4 s(1, 2, 3);
}