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#include <iostream> #include <vector> using namespace std; // 拥有一个或多个纯虚函数的类，称为抽象类 // 抽象类应该将析构函数定义为虚函数，这样在delete抽象类指针的时候， // 派生类和抽象类的析构函数才能都被调用 class Shap { public: virtual void Draw() = 0; virtual ~Shap() {} }; class Circle : public Shap { public: void Draw() { cout << "Circle Draw ..." << endl; } ~Circle() { cout << "Circle Destructor" << endl; } }; class Square : public Shap { public: void Draw() { cout << "Square Draw ..." << endl; } ~Square() { cout << "Square Destructor" << endl; } }; void DrawAllShap(const vector<Shap*>& vecShap) { vector<Shap*>::const_iterator it; for (it = vecShap.begin(); it != vecShap.end(); ++it) (*it)->Draw(); } void DeleteAllShap(const vector<Shap*>& vecShap) { vector<Shap*>::const_iterator it; for (it = vecShap.begin(); it != vecShap.end(); ++it) delete(*it); } int main() { // Shap shap; // 不能实例化抽象类 vector<Shap*> vecShap; Shap* shap; shap = new Circle; vecShap.push_back(shap); shap = new Square; vecShap.push_back(shap); DrawAllShap(vecShap); DeleteAllShap(vecShap); return 0; } |
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