设计模式之原型模式，C++实现

原创：http://blog.csdn.net/iuhsihsow

其实个人觉得原型模式在C++也就那样吧。反正设计一个类，如果有需要都会重载=或者设置深拷贝函数。

所以就简单写一下吧。

示意图，UML还是不太会

代码：

#include "stdafx.h"
 #include <memory.h>
 #include <stdio.h>
 #include <string.h>
 #include <locale.h>
 #include <iostream>




 // 原型模式其实就是从一个对象再创建另外一个可定制的对象，而且不需要知道任何创建的细节


 // 问1：和deepCopy有什么区别？重载"="或者写一个DeepCopy函数就可以了嘛？
 // 问2：貌似没有最大限度的节省内存，要节省内存是不是要用享元模式？
 // 问3：C++里面可没有什么MemberwiseClone()



 // 假设情景，某游戏，当用户新建角色时，会出现一个基础角色，
 // 然后用户再在此基础上对该基础角色进行修改
 // （其实应该是根据玩家的性别，身形选择，大致创建一个基础的角色外形，然后由玩家装扮，本处简化）

 // char *纯粹是用于深拷贝

 #define DELETE_OBJECT(p){ if (p) delete p;p = NULL; }

 enum ESex
 {
 male,
 famale
 };

 class IRole
 {
 public:
 virtual void Setproperty(ESex eSex, int nAge) = 0;
 virtual void SetDescription(char * pDescpt, int nLength) = 0;
 virtual void Show() = 0;
 virtual IRole* Clone() = 0;
 virtual void SetName(const std::string &strName) = 0;

 protected:
 std::string m_strName;
 ESexm_eSex;
 intm_nAge;
 char*m_pDescription;
 intm_nDscriptLength;

 };

 class BaseRole : public IRole
 {
 public:
 BaseRole()
 //: m_eSex(male)
 //, m_nAge(25)
 //, m_pDescription(NULL)
 {
 m_eSex = male;
 m_nAge = 25;
 m_pDescription = NULL;
 }
 virtual ~BaseRole()
 {
 DELETE_OBJECT(m_pDescription);
 }

 void SetName(const std::string &strName)
 {
 m_strName = strName;
 }
 void Setproperty(ESex eSex, int nAge)
 {
 m_eSex = eSex;
 m_nAge = nAge;
 }
 void SetDescription(char * pDescpt, int nLength)
 {
 m_nDscriptLength = nLength;
 m_pDescription = new char[nLength + 1];
 memset(m_pDescription, 0, nLength + 1);
 memcpy(m_pDescription, pDescpt, nLength);
 }
 void Show()
 {
 printf("\n\nNow Show A Role Information:\n");
 printf("Name:%s\n", m_strName.c_str());
 if (male == m_eSex)
 {
 printf("Sex: Male\n");
 }
 else
 {
 printf("Sex: FeMale\n");
 }
 printf("Age :%d\n", m_nAge);
 printf(m_pDescription);
 printf("\n");
 }
 IRole* Clone()
 {
 BaseRole * pRole = new BaseRole;
 pRole->m_eSex = m_eSex;
 pRole->m_nAge = m_nAge;
 pRole->m_strName = m_strName;
 pRole->m_nDscriptLength = m_nDscriptLength;
 pRole->m_pDescription = new char[m_nDscriptLength + 1];
 memset(pRole->m_pDescription, 0, m_nDscriptLength + 1);
 memcpy(pRole->m_pDescription, m_pDescription, m_nDscriptLength);
 return pRole;
 }

 protected:
 private:
 };


 int _tmain(int argc, _TCHAR* argv[])
 {

 //创建描述语句
 char *pChar = "So clever!";
 int nLength = strlen(pChar);

 char *pChar_1 = "A Nice People!";
 int nLength_1 = strlen(pChar_1);

 //创建BaseRole
 BaseRole *pBase = new BaseRole;
 pBase->Setproperty(male, 15);
 pBase->SetDescription(pChar, nLength);
 pBase->SetName("BaseRole");

 //根据BaseRole创建其他
 BaseRole *pTom = (BaseRole*)pBase->Clone();
 pTom->SetDescription(pChar_1, nLength_1);
 pTom->SetName("Tom");

 BaseRole *pLucy = dynamic_cast<BaseRole*>(pBase->Clone());
 pLucy->Setproperty(famale, 18);
 pLucy->SetName("Lucy");

 pBase->Show();
 pTom->Show();
 pLucy->Show();

 DELETE_OBJECT(pBase);
 DELETE_OBJECT(pTom);
 DELETE_OBJECT(pLucy);

 return 0;
 }

 /*结果
 Now Show A Role Information:
 Name:BaseRole
 Sex: Male
 Age :15
  So clever!


  Now Show A Role Information:
 Name:Tom
 Sex: Male
 Age :15
  A Nice People!


  Now Show A Role Information:
 Name:Lucy
 Sex: FeMale
 Age :18
  So clever!
  请按任意键继续. . .
 */