嘿嘿,你这个问题很不错,我根据你的代码写了几行,你参考着来吧。这个思路是从MFC来的,有空你可以看看相关的资料以及类工厂思想
#include <map>
class pic
{
public:
typedef pic *(*children)();
static pic *create(const int classId)
{
std::map<const int,children>::iterator it=_myChildren.find(classId);
return (it==_myChildren.end())?NULL:(it->second)();
}
protected:
static void _register(const int classId,children classDerived)
{
_myChildren.insert(std::map<const int,children>::value_type(classId,classDerived));
}
private:
static std::map<const int,children> _myChildren;
public:
virtual void load()=0;
};
std::map<const int,pic::children> pic::_myChildren;
//两个关键的宏定义
//声明
#define DECLEAR_DYNCRT_PICCLASS(derived,classId)\
public:\
struct derived##register\
{\
derived##register()\
{\
static bool bRegister=false;\
if (!bRegister)\
{\
pic::_register(classId,_createObject);\
bRegister=true;\
}\
}\
};\
static pic* _createObject()\
{\
return new derived;\
}
//实现
#define IMPLEMENT_DYNCRT_PICCLASS(derived) \
static derived::derived##register _##derived##object;
#include <iostream>
using namespace std;
class pic1:public pic
{
DECLEAR_DYNCRT_PICCLASS(pic1,1) //声明动态类
public:
virtual void load()
{
cout<<"pic1 load"<<endl;
}
};
IMPLEMENT_DYNCRT_PICCLASS(pic1) //实现
class pic2:public pic
{
DECLEAR_DYNCRT_PICCLASS(pic2,2) //声明动态类
public:
virtual void load()
{
cout<<"pic2 load"<<endl;
}
};
IMPLEMENT_DYNCRT_PICCLASS(pic2) //实现
class pic3 :public pic
{
DECLEAR_DYNCRT_PICCLASS(pic3,3) //声明动态类
public:
virtual void load()
{
cout<<"pic3 load"<<endl;
}
};
IMPLEMENT_DYNCRT_PICCLASS(pic3) //实现
int main()
{
pic *p1=pic::create(1);
p1->load();
pic *p2=pic::create(2);
p2->load();
pic *p3=pic::create(3);
p3->load();
return 0;
}