c++ typeid 注意事项

typeid
对于不含有虚函数的类对象,无法识别
对于含有虚函数的对象能够识别

无法准确识别任何指针对象

#include "stdafx.h"
#include <iostream>
#include <string>

using namespace std;

class BaseNoVirtual
{
};

class DeriveNoVirtual
    :public BaseNoVirtual
{

};

class BaseVirtual
{
public:
    virtual int VirtualFn()
    {
        return 0;
    }
};

class DeriveVirtual
    :public BaseVirtual
{
public:
    int VirtualFn()
    {
        return 1;
    }
};

string WhoAreYou_PointNoVirtual(BaseNoVirtual* a_p)
{
    return typeid(a_p).name();
}
string WhoAreYou_NoVirtual(BaseNoVirtual* a_p)
{
    return typeid(*a_p).name();
}

string WhoAreYou_PointVirtual(BaseVirtual* a_p)
{
    return typeid(a_p).name();
}
string WhoAreYou_Virtual(BaseVirtual* a_p)
{
    return typeid(*a_p).name();
}
int main()
{

    auto bnv = BaseNoVirtual();
    auto dnv = DeriveNoVirtual();
    cout << "BaseNoVirtual   对象:  " << typeid(bnv).name() << endl;
    cout << "DeriveNoVirtual 对象:  " << typeid(dnv).name() << endl;

    auto pbnv = new BaseNoVirtual();
    auto pdnv = new DeriveNoVirtual();

    cout << "BaseNoVirtual   指针:  " << typeid(pbnv).name() << endl;
    cout << "DeriveNoVirtual 指针:  " << typeid(pdnv).name() << endl;

    cout << "BaseNoVirtual   PVOID指针:  " << typeid((void*)pbnv).name() << endl;
    cout << "DeriveNoVirtual PVOID指针:  " << typeid((void*)pdnv).name() << endl;

    cout << "BaseNoVirtual   函数无虚基类指针:  " << WhoAreYou_PointNoVirtual(pbnv) << endl;
    cout << "DeriveNoVirtual 函数无虚基类指针:  " << WhoAreYou_PointNoVirtual(pdnv) << endl;

    cout << "BaseNoVirtual   函数无虚基类对象:  "<< WhoAreYou_NoVirtual(pbnv) << endl;
    cout << "DeriveNoVirtual 函数无虚基类对象:  " << WhoAreYou_NoVirtual(pdnv) << endl;

    cout << endl << endl << endl;


    auto bv = BaseVirtual();
    auto dv = DeriveVirtual();
    cout << "BaseVirtual   对象:  " << typeid(bv).name() << endl;
    cout << "DeriveVirtual 对象:  " << typeid(dv).name() << endl;

    auto pbv = new BaseVirtual();
    auto pdv = new DeriveVirtual();

    cout << "BaseVirtual   指针:  " << typeid(pbv).name() << endl;
    cout << "DeriveVirtual 指针:  " << typeid(pdv).name() << endl;

    cout << "BaseVirtual   PVOID指针:  " << typeid((void*)pbv).name() << endl;
    cout << "DeriveVirtual PVOID指针:  " << typeid((void*)pdv).name() << endl;

    cout << "BaseVirtual   函数有虚基类指针:  " << WhoAreYou_PointVirtual(pbv) << endl;
    cout << "DeriveVirtual 函数有虚基类指针:  " << WhoAreYou_PointVirtual(pdv) << endl;

    cout << "BaseVirtual   函数有虚基类对象:  " << WhoAreYou_Virtual(pbv) << endl;
    cout << "DeriveVirtual 函数有虚基类对象:  " << WhoAreYou_Virtual(pdv) << endl;
    return 0;
}

BaseNoVirtual 对象: class BaseNoVirtual
DeriveNoVirtual 对象: class DeriveNoVirtual
BaseNoVirtual 指针: class BaseNoVirtual * __ptr64
DeriveNoVirtual 指针: class DeriveNoVirtual * __ptr64
BaseNoVirtual PVOID指针: void * __ptr64
DeriveNoVirtual PVOID指针: void * __ptr64
BaseNoVirtual 函数无虚基类指针: class BaseNoVirtual * __ptr64
DeriveNoVirtual 函数无虚基类指针: class BaseNoVirtual * __ptr64
BaseNoVirtual 函数无虚基类对象: class BaseNoVirtual
DeriveNoVirtual 函数无虚基类对象: class BaseNoVirtual

BaseVirtual 对象: class BaseVirtual
DeriveVirtual 对象: class DeriveVirtual
BaseVirtual 指针: class BaseVirtual * __ptr64
DeriveVirtual 指针: class DeriveVirtual * __ptr64
BaseVirtual PVOID指针: void * __ptr64
DeriveVirtual PVOID指针: void * __ptr64
BaseVirtual 函数有虚基类指针: class BaseVirtual * __ptr64
DeriveVirtual 函数有虚基类指针: class BaseVirtual * __ptr64
BaseVirtual 函数有虚基类对象: class BaseVirtual
DeriveVirtual 函数有虚基类对象: class DeriveVirtual