NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c++-part2/15944

Internet Message Format | 1996-08-05 | 1.7 KB

Path: ix.netcom.com!netnews
From: [e-mail]@ix.netcom.com   (Van Chinh Ly)
Newsgroups: comp.lang.c++
Subject: Re: How do I put DIFFERENT classes in the same linked list?
Date: 8 Apr 1996 06:44:35 GMT
Organization: Netcom
Message-ID: <4kackj$[e-mail]>
References: <4ka938$[e-mail]>
Reply-To: [e-mail]
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X-NETCOM-Date: Sun Apr 07 11:44:35 PM PDT 1996
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In <4ka938$[e-mail]>, grosin@titan (Gil Rosin) writes:
>...
>
>#include <iostream.h>
>
>class A
> {
>  public:
>    A *next;
>    A *prev;
>    void Print();
> };
>
>class Demo
> {
>  public:
>    void Insert(A *Temp);
>    void Insert2(A *Temp);
>    void Test(void);
>    A *First;
> };
>
>class B : public A
> {
>  void Print();
> };
>
>class C : public A
> {
>  void Print();
> };
>
>main()
> {
>  Demo *T = new Demo;
>  A *Test = new B;
>  T->Insert(Test);
>  Test = new C;
>  T->Insert2(Test);
>  T->Test();
>  return 0;
> }
>
>void B::Print()
> {
>  cout << "I am in class B" << '\n';
> }
>
>void C::Print()
> {
>  cout << "I am in class C" << '\n';
> }
>
>...
>
>Now, as you can see, I want to have a linked list that contains EITHER
>B or C Items, but in the void Demo::Test() function, I want to be able to
>just call them blindly with out knowing which is which. When I compile this
>I get NO errors, but when I run it the two lines that print out are the
>class A print function. It should print out the class B and then the class C.
>
>How can I do this? I am not worrying about constructors/destructors etc
>right now, just worrying about how to get it to work.
>

Is this homework?  :)

Check out "virtual functions."


Van