typeid.cpp

来自「本课程主要介绍面向对象程序设计的方法和c++语言的基本概念。以c++语言中的面向」· C++ 代码 · 共 32 行

// typeid.cpp
// demonstrates typeid() function
// RTTI must be enabled in compiler
#include <iostream>
#include <typeinfo>           //for typeid()
using namespace std;
////////////////////////////////////////////////////////////////
class Base
   {
   virtual void virtFunc()    //needed for typeid
      {  }
   };
class Derv1 : public Base
   { };
class Derv2 : public Base
   { };
////////////////////////////////////////////////////////////////
void displayName(Base* pB)
   {
   cout << "pointer to an object of: ";  //display name of class
   cout << typeid(*pB).name() << endl;  //pointed to by pB
   }
//--------------------------------------------------------------
int main()
   {
   Base* pBase = new Derv1;
   displayName(pBase);   //"pointer to an object of class Derv1"

   pBase = new Derv2;
   displayName(pBase);   //"pointer to an object of class Derv2"
   return 0;
   }