c++组合模式

组合模式：允许你将对象组合成树形结构来表现“整体/部分”层次结构。组合能让客户以一致的方式处理个别对象以及对象组合。

代码：

#pragma once #pragma warning(disable : 4996) #include <iostream> #include <assert.h> #include <vector> using namespace std; class menuComponent { public: virtual void add(menuComponent* m) { assert(false); } virtual void remove(menuComponent* m) { assert(false); } virtual menuComponent* getChild(int i) { return NULL; } virtual string getName(menuComponent* m) { return "no name"; } virtual string getDescription() { return "no description"; } virtual double getPrice() { return 0.0; } virtual bool isVegetarian() { return false; } virtual void print() { assert(false); } }; class menuItem :public menuComponent { string name; string description; bool vegetarian; double price; public: menuItem(string nn, string dd, bool vv, double pp) { name = nn; description = dd; vegetarian = vv; } string getName() { return name; } string getDescription() { return description; } double getPrice() { return price; } bool isVegetarian() { return vegetarian; } void print() { cout << "name:" << getName() << endl; if (isVegetarian()) cout << "Vegetarian:true"; else cout << "Vegetarian:false"; } }; class menu :public menuComponent { vector<menuComponent*> mu; string name; string description; public: menu(string nn, string dd) { name = nn; description = dd; } void add(menuComponent* m) { mu.push_back(m); } void remove(menuComponent* m) { mu.pop_back(); } menuComponent* getChild(int i) { return mu.at(i); } string getName() { return name; } string getDescription() { return description; } void print() { cout << "name:" << getName() << endl; cout << "description:" << getDescription() << endl; cout << "*****************" << endl; vector<menuComponent*>::iterator it = mu.begin(); for (it; it != mu.end(); it++) { (*it)->print(); } } }; int main() { menuComponent* pancakeHouseMenu = new menu("pancake house menu", "breakfase"); menuComponent* dinerMenu = new menu("diner menu", "lunch"); menuComponent* cafeMenu = new menu("cafe menu", "diner"); menuComponent* allmenu = new menu("all menu", "all menus combined"); allmenu->add(pancakeHouseMenu); allmenu->add(dinerMenu); allmenu->add(cafeMenu); pancakeHouseMenu->add(new menuItem("pancake", "pancake description", false, 20)); dinerMenu->add(new menuItem("diner", "diner description", false, 10.5)); cafeMenu->add(new menuItem("cafe", "cafe description", true, 8.35)); allmenu->print(); }

结果：