Материал из C\C++ эксперт
Granting Access: Inherit base as private
#include <iostream>
using namespace std;
class base {
int i; // private to base
public:
int j, k;
void seti(int x) { i = x; }
int geti() { return i; }
};
// Inherit base as private.
class derived: private base {
public:
base::j; // make j public again - but not k
base::seti; // make seti() public
base::geti; // make geti() public
int a; // public
};
int main()
{
derived ob;
ob.j = 20; // legal because j is made public in derived
ob.a = 40; // legal because a is public in derived
ob.seti(10);
cout << ob.geti() << " " << ob.j << " " << ob.a;
return 0;
}how to use an access declaration
#include <iostream>
using namespace std;
class B_class {
public:
int i, j;
};
class D_class : private B_class {
public:
// access declaration
B_class::i; // i from B_class is now public again
int k;
} ;
main(void)
{
D_class d;
d.i = 10; // legal because i is made public in D_class
d.k = 20;
cout << d.i * d.k;
return 0;
}Inherit base as private
#include <iostream>
using namespace std;
class base {
private:
int i;
public:
int j, k;
void seti(int x) { i = x; }
int geti() { return i; }
};
class derived: private base {
public:
base::j;
base::seti;
base::geti;
int a;
};
int main()
{
derived ob;
ob.j = 20; // legal because j is made public in derived
//ob.k = 30; // illegal because k is private in derived
ob.a = 40; // legal because a is public in derived
ob.seti(10);
cout << ob.geti() << " " << ob.j << " " << ob.a;
return 0;
}10 20 40"
