Hello
I have problem using class base with pure virtual method. The method should be virtual.
I get this error:
Member is class base.Error: object of abstract class type "Membro" is not allowed: function "Member::sale" is a pure virtual function
- Teacher (derived)
- Student (derived)
I'm creating a new object to trying find, but how the method is abstract i can't do that.
What's the suggestion to solve my problem?
Thanks!
You are trying to make objects of the base class.
When there is a (pure) virtual function, objects of derived classes make sense.
The base class is only there as some sort of common interface.
Btw, next time, post your code too.
member is a collection of members
I want find member, but first i need create..How can i do that without create object?Code:Member *Sop::findMember(string bi){ Member *m = new Member(bi, NULL); return member.find(m) }
Thanks!
Since Member has pure virtual functions, you must create instances of the derived classes.
Code:Member *Sop::findMember(string bi){ Member *m = new Student(bi, NULL); // Note that we are now creating a Student instead of a Member return member.find(m) }
bit∙hub [bit-huhb] n. A source and destination for information.
Thanks, problem solved.Originally Posted by bithub
You might want to rename it members or maybe member_collection. It would be better if you actually showed the definition of this object: many things in C++ depends on type, and "a collection of members" does not tell us much about the type.
It might be feasible to just write:
Otherwise say, std::unique pointer should be used, or at the very least one should manually have a delete to match the new.Code:Member* Sop::findMember(string bi) { Student student(bi, NULL); return member.find(&student); }
Look up a C++ Reference and learn How To Ask Questions The Smart Way
