Dynamically creating an instance of a class from a string containing the class name in C++

Question

Lets say I have a base class with 100 children:

class Base { 
  virtual void feed();
  ...   
};
class Child1 : public Base {
  void feed();  //specific proc         


        

Answer 1

If you have a lot of classes, you'd usually choose a less brute force approach. A trie or hash_map between class names and factory functions is a good approach.

You can use a codegen approach as suggested by Greg to build this factory table, for example doxygen can parse your source code and output a list of all classes in xml format along with inheritance relationships, so you could easily find all classes deriving from a common "interface" base class.