Use dynamic_cast to replace typeid : dynamic_cast « Pointer « C++ Tutorial

Home
C++ Tutorial
1.Language Basics
2.Data Types
3.Operators statements
4.Array
5.Development
6.Exceptions
7.Function
8.Structure
9.Class
10.Operator Overloading
11.Pointer
12.File Stream
13.template
14.STL Introduction
15.string
16.vector
17.list
18.bitset
19.set multiset
20.valarray
21.queue stack
22.deque
23.map multimap
24.STL Algorithms Modifying sequence operations
25.STL Algorithms Non modifying sequence operations
26.STL Algorithms Binary search
27.STL Algorithms Sorting
28.STL Algorithms Merge
29.STL Algorithms Min Max
30.STL Algorithms Iterator
31.STL Algorithms Heap
32.STL Algorithms Helper
C / ANSI-C
C Tutorial
C++
Visual C++ .NET
C++ Tutorial » Pointer » dynamic_cast 
11.6.2.Use dynamic_cast to replace typeid
#include <iostream>
#include <typeinfo>
using namespace std;

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

class Derived : public Base {
public:
  void derivedOnly() {
    cout << "Is a Derived Object.\n";
  }
};

int main()
{
  Base *bp, b_ob;
  Derived *dp, d_ob;

  // use typeid
  bp = &b_ob;
  if(typeid(*bp== typeid(Derived)) {
    dp = (Derived *bp;
    dp->derivedOnly();
  }
  else
    cout << "Cast from Base to Derived failed.\n";

  return 0;
}
Cast from Base to Derived failed.
11.6.dynamic_cast
11.6.1.Dynamic cast
11.6.2.Use dynamic_cast to replace typeid
11.6.3.dynamic_cast: Cast from Base * to Derived * (wrong)
11.6.4.dynamic_cast: Cast from Base * to Base *
11.6.5.dynamic_cast: Cast from Derived * to Derived *
11.6.6.dynamic_cast: Cast from Derived * to Base *
www.java2java.com | Contact Us
Copyright 2009 - 12 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.