//main.h头文件
#pragma once
#include"a.h"
class CShape
{
public:
virtual CRuntimeClassTest* GetRuntimeClassTest() const;
BOOL IsKindOf(const CRuntimeClassTest* pClass) const;
public:
static CRuntimeClassTest classCShape;
};
static char szCShape[] = "CShape";
struct CRuntimeClassTest CShape::classCShape = { szCShape ,sizeof(szCShape),0xffff,NULL,NULL};
static CLASS_INIT init_CShape(&CShape::classCShape);
CRuntimeClassTest* CShape::GetRuntimeClassTest() const
{
return &CShape::classCShape;
}
inline BOOL CShape::IsKindOf(const CRuntimeClassTest * pClass) const
{
CRuntimeClassTest* pClassThis = GetRuntimeClassTest();
while (pClassThis!= NULL)
{
if (pClassThis == pClass)
return TRUE;
pClassThis = pClassThis->m_pBaseClass;
}
return FALSE;
}
//a.h头文件
#pragma once
#include<afxwin.h>
class CShape;
//RTTI结构体
struct CRuntimeClassTest
{
LPCSTR m_lpszClassName;
int m_nObjectSize;
UINT m_wSchema;
CShape*(PASCAL*m_pfnCreateShape)();
CRuntimeClassTest* m_pBaseClass;
static CRuntimeClassTest* pFirstClass;
CRuntimeClassTest* m_pNextClass;
};
struct CLASS_INIT
{
//c++struct也有构造函数
CLASS_INIT(CRuntimeClassTest* pNewClass);
};
//下面为几组宏,由于文字代换
/*
*宏定义,"\"指换行,后面的语句和它是一个部分的。
*其中##告诉编译器把左右连个字符串连接在一起,即把class和参数class_name的值连接在一起。
*/
#define TyPeName(class_name)\
public:\
static CRuntimeClassTest class##class_name;\
virtual CRuntimeClassTest* GetRuntimeClassTest() const;
#define RUN_TIME_CLASS(class_name)\
(&class_name::class##class_name)
#define DYNAMIC_RUNTIMECLASS(class_name,baseclass_name,wSchema,pfnNew)\
static char lpsz##class_name[]=#class_name;\
CRuntimeClassTest class_name::class##class_name={\
lpsz##class_name,sizeof(class_name),wSchema,pfnNew,RUN_TIME_CLASS(baseclass_name),NULL};\
static CLASS_INIT init_##class_name(&class_name::class_name::class##class_name);\
CRuntimeClassTest* class_name::GetRuntimeClassTest() const\
{return &class_name::class##class_name;}
/*
*用于动态创建对象的宏
*/
#define DYNAMIC_CREATE(class_name,baseclass_name)\
DYNAMIC_RUNTIMECLASS(class_name,baseclass_name,0xFFFF,NULL)
CLASS_INIT::CLASS_INIT(CRuntimeClassTest * pNewClass)
{
pNewClass->m_pNextClass = CRuntimeClassTest::pFirstClass;
CRuntimeClassTest::pFirstClass = pNewClass;
}
//main.cpp
#pragma once
#include"a.h"
#include"main.h"
#include<iostream>
using namespace std;
CRuntimeClassTest* CRuntimeClassTest::pFirstClass = NULL;//静态成员变量初始化的位置
class CCircle :public CShape
{
TyPeName(CCircle)
};
class CEllipse :public CCircle
{
TyPeName(CEllipse)
};
DYNAMIC_CREATE(CCircle,CShape)
DYNAMIC_CREATE(CEllipse,CCircle)
void Print()
{
CRuntimeClassTest* pClass;
for (pClass = CRuntimeClassTest::pFirstClass; pClass != NULL; pClass = pClass->m_pNextClass)
{
cout << pClass->m_lpszClassName << "," << pClass->m_nObjectSize << "," << pClass->m_wSchema << endl;
}
}
int main()
{
CEllipse* pE = new CEllipse;
CCircle* pC = new CCircle;
Print();
if (pE->IsKindOf(RUN_TIME_CLASS(CEllipse)))
{
cout << "对象pE的类型为:CEllipse" << endl;
}
if (pC->IsKindOf(RUN_TIME_CLASS(CShape)))
{
cout << "对象pC的类型为CShape" << endl;
}
delete pE;
delete pC;
return 0;
}
若代码改为如下图,则运行结果如下:
if (pE->IsKindOf(RUN_TIME_CLASS(CEllipse)))
{
cout << "对象pE的类型为:CEllipse" << endl;
}
if (pC->IsKindOf(RUN_TIME_CLASS(CEllipse)))
{
cout << "对象pC的类型为CShape" << endl;
}