设计模式C++版：第九式组合模式

组合模式：将对象组合成树形结构以表示部分和整体的关系。组合模式使得用户对单个对象和组合对象的使用具有一致性。优点：基本对象可以组合成更复杂的对象。任何用到基本对象的地方，都可以使用组合对象。示例代码：

#include <string>
using std::string;
#include <list>
using std::list;

class CTest
{
public:
	CTest(string name) :m_name(name){	}
	virtual ~CTest(){ }
	virtual void add(CTest* CTest){	}
	virtual void remove(CTest* CTest){	}
	virtual void display(int depth){	}
	virtual void lineofduty(){	}
protected:
	string m_name;
private:

};


class ConcreteTest :public CTest
{
public:
	ConcreteTest(string name) :CTest(name){	}

	~ConcreteTest()
	{
		while (true){
			if (!m_childrenList.empty()){
				delete *m_childrenList.begin();
			}
			else{
				break;
			}
		}

	}

	void add(CTest* CTest)override
	{
		m_childrenList.push_back(CTest);
	}

	void remove(CTest* CTest)override
	{
		m_childrenList.remove(CTest);
	}

	void display(int depth)override
	{
		printf("%d,%s\n", depth, m_name.c_str());
		for each  (CTest* var in m_childrenList){
			var->display(depth + 2);
		}
	}

	void lineofduty()override
	{
		for each  (CTest* var in m_childrenList){
			var->lineofduty();
		}
	}

private:
	list<CTest*>m_childrenList;
};


class LeafTest :public CTest
{
public:
	LeafTest(string name) :CTest(name){	}

	void add(CTest* CTest)override{	}

	void remove(CTest* CTest){	}

	void display(int depth)override
	{
		printf("%d,%s\n", depth, m_name.c_str());
	}

	void lineofduty()
	{
		printf("组合树的叶子\n");
	}

};

int main()
{
	ConcreteTest *root = new ConcreteTest("跟节点");

	root->add(new LeafTest("叶子一"));

	ConcreteTest* test1 = new ConcreteTest("子节点一");
	test1->add(new LeafTest("子叶子一"));
	root->add(test1);

	ConcreteTest* test2 = new ConcreteTest("孙节点一");
	test2->add(new LeafTest("孙叶子一"));
	test1->add(test2);

	printf("树的结构是-----------------\n");
	root->display(1);

	return 0;
}