49 lines
721 B
C++
49 lines
721 B
C++
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// 友元
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// 友元的类成员函数
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#include <iostream>
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#include <cstring>
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#include <cstdlib>
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using namespace std;
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class B;
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class C
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{
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public:
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// 在此函数内，要访问 B 类中的所有成员，将此函数在 B 类中声明友元
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// 先声明，不能实现
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void showB(B &b);
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};
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class B
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{
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// 声明友元的成员函数
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friend void C::showB(B &b);
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private:
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int x;
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public:
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B(int x) : x(x) {}
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void show()
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{
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cout << "成员函数 x = " << x << endl;
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}
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};
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// 定义或实现友元的成员函数
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void C::showB(B &b)
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{
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cout << "友元的成员函数 b.x = " << b.x << endl;
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}
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int main()
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{
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B b(100);
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b.show();
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C c;
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c.showB(b);
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return 0;
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}
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