C++抽象类实践

实践如下：

#include <iostream>

using namespace std;

class Service {

public:

    // 有一个虚函数即为抽象类

    int id;

    // 不定义虚析构函数 会报右侧异常：@suppress("Class has a virtual method and non-virtual destructor")

    virtual ~Service(){}

    virtual double calc()=;

    int aa(){

        return ;

    }

};

class AService: public Service {

public:

    //virtual ~AService(){}

    double calc() {

        // 操作抽象类中定义的字段

        id = ;

        cout << "id：" << id << endl;

        cout << "AService 100~~~" << endl;

        return ;

    }

};

class BService: public Service {

public:

    //virtual ~BService(){}

    double calc() {

        cout << "BService 200~~~" << endl;

        return ;

    }

};

int main() {

    cout << "抽象类 实践：" << endl;

    Service *s = new AService();

    s->calc();

    cout << "\n抽象类 end." << endl;

    return ;

}

结果：