c++中那些奇怪的事情

content {:toc}

引用来实现多态

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#include<iostream>
using namespace std;

class Base {
public:
    virtual void print() {
        cout << "This is Base class." << endl;
    }
};

class Derived : public Base {
public:
    void print() {
        cout << "This is Derived class." << endl;
    }
};

int main() {
    Derived derivedObj;
    Base& baseRef = derivedObj;  // 使用基类引用引用派生类对象

    baseRef.print();  // 调用的是 Derived 类中的 print 函数

    return 0;
}

不涉及多态时, 删除对象会发生什么

结果, 还能运行函数

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#include<iostream>
using namespace std;

class Base {
public:
     void print() {
        cout << "This is Base class." << endl;
    }
};



int main() {
    Base * p = new Base();
  delete(p);
  p-> print();
  cout<< "success"<< '\n';
}

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#include<iostream>
using namespace std;

class Base {
public:
     void print() {
        cout << "This is Base class." << endl;
       cout<< "a = "<< a <<'\n';
    }
  int a = 0;
};



int main() {
    Base * p = new Base();
  p->print(); // a = 0;
  delete(p); 
  p-> print(); // a = 5898


    return 0;
}