typeid 一节

好久都说要好好测测typeid的用法，今天终于得以如愿以偿，呵呵。下面，我就把测试代码发下来，

#include <typeinfo>
#include <iostream>

using namespace std;

class Base
{
public:
 virtual void vvFcn(){}
};

class Derived : public Base
{
public:
 virtual void vvFcn(){}
};
int main()
{
 Derived *pd = new Derived;
 Base *pb = pd;
 cout << typeid(pb).name() << endl;
 cout << typeid(*pb).name() << endl;
 cout << typeid(pd).name() << endl;

cout << (typeid(int) == typeid(int&)) << endl;

 

return 0;
}

测试结果如下所示，

class Base*

class Derived

class Derived*

1

The typeid operator produces a reference to an object of class type_info, which describes the most-derived type of the object. In order to make use of the typeid() function, source code must #include the <typeinfo.h> header file. The primary value of this operator/class combination is in comparisons. In such comparisons, the top-level const-volatile qualifiers are ignored