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copied!<p>Using something like <a href="http://www.boost.org/doc/libs/1_41_0/libs/serialization/doc/index.html" rel="noreferrer">Boost Serialization</a>, while by no means a standard, is a (for the most part) very well written library that does the grunt work for you.</p> <p>The last time I had to manually parse a predefined record structure with a clear inheritance tree, I ended up using the <a href="http://en.wikipedia.org/wiki/Factory_pattern" rel="noreferrer">factory pattern</a> with registrable classes (i.e. Using a map of key to a (template) creator function rather than a lot of switch functions) to try and avoid the issue you were having.</p> <p><strong>EDIT</strong><br> A basic C++ implementation of a object factory mentioned in the above paragraph.</p> <pre><code>/** * A class for creating objects, with the type of object created based on a key * * @param K the key * @param T the super class that all created classes derive from */ template<typename K, typename T> class Factory { private: typedef T *(*CreateObjectFunc)(); /** * A map keys (K) to functions (CreateObjectFunc) * When creating a new type, we simply call the function with the required key */ std::map<K, CreateObjectFunc> mObjectCreator; /** * Pointers to this function are inserted into the map and called when creating objects * * @param S the type of class to create * @return a object with the type of S */ template<typename S> static T* createObject(){ return new S(); } public: /** * Registers a class to that it can be created via createObject() * * @param S the class to register, this must ve a subclass of T * @param id the id to associate with the class. This ID must be unique */ template<typename S> void registerClass(K id){ if (mObjectCreator.find(id) != mObjectCreator.end()){ //your error handling here } mObjectCreator.insert( std::make_pair<K,CreateObjectFunc>(id, &createObject<S> ) ); } /** * Returns true if a given key exists * * @param id the id to check exists * @return true if the id exists */ bool hasClass(K id){ return mObjectCreator.find(id) != mObjectCreator.end(); } /** * Creates an object based on an id. It will return null if the key doesn't exist * * @param id the id of the object to create * @return the new object or null if the object id doesn't exist */ T* createObject(K id){ //Don't use hasClass here as doing so would involve two lookups typename std::map<K, CreateObjectFunc>::iterator iter = mObjectCreator.find(id); if (iter == mObjectCreator.end()){ return NULL; } //calls the required createObject() function return ((*iter).second)(); } }; </code></pre>

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