typeid
對於不含有虛擬函式的類物件,無法識別
對於含有虛擬函式的物件能夠識別

無法準確識別任何指標物件

#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   物件:  " << typeid(bnv).name() << endl;
    cout << "DeriveNoVirtual 物件:  "
 
 << typeid(dnv).name() << endl;

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

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

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

    cout << "BaseNoVirtual   函式無虛基類指標:  " << WhoAreYou_PointNoVirtual(pbnv) << endl;
    cout << "DeriveNoVirtual 函式無虛基類指標:  " << WhoAreYou_PointNoVirtual(pdnv) << endl;

    cout << "BaseNoVirtual   函式無虛基類物件:  "<< WhoAreYou_NoVirtual(pbnv) << endl;
    cout << "DeriveNoVirtual 函式無虛基類物件:  " << WhoAreYou_NoVirtual(pdnv) << endl;

    cout << endl << endl << endl;


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

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

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

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

    cout << "BaseVirtual   函式有虛基類指標:  " << WhoAreYou_PointVirtual(pbv) << endl;
    cout << "DeriveVirtual 函式有虛基類指標:  " << WhoAreYou_PointVirtual(pdv) << endl;

    cout << "BaseVirtual   函式有虛基類物件:  " << WhoAreYou_Virtual(pbv) << endl;
    cout << "DeriveVirtual 函式有虛基類物件:  " << WhoAreYou_Virtual(pdv) << endl;
    return 0;
}

BaseNoVirtual 物件: class BaseNoVirtual
DeriveNoVirtual 物件: class DeriveNoVirtual
BaseNoVirtual 指標: class BaseNoVirtual * __ptr64
DeriveNoVirtual 指標: class DeriveNoVirtual * __ptr64
BaseNoVirtual PVOID指標: void * __ptr64
DeriveNoVirtual PVOID指標: void * __ptr64
BaseNoVirtual 函式無虛基類指標: class BaseNoVirtual * __ptr64
DeriveNoVirtual 函式無虛基類指標: class BaseNoVirtual * __ptr64
BaseNoVirtual 函式無虛基類物件: class BaseNoVirtual
DeriveNoVirtual 函式無虛基類物件: class BaseNoVirtual

BaseVirtual 物件: class BaseVirtual
DeriveVirtual 物件: class DeriveVirtual
BaseVirtual 指標: class BaseVirtual * __ptr64
DeriveVirtual 指標: class DeriveVirtual * __ptr64
BaseVirtual PVOID指標: void * __ptr64
DeriveVirtual PVOID指標: void * __ptr64
BaseVirtual 函式有虛基類指標: class BaseVirtual * __ptr64
DeriveVirtual 函式有虛基類指標: class BaseVirtual * __ptr64
BaseVirtual 函式有虛基類物件: class BaseVirtual
DeriveVirtual 函式有虛基類物件: class DeriveVirtual