Factory vs instance constructors

Question

I can\'t think of any reasons why one is better than the other. Compare these two implementations:

public class MyClass
{
    public MyClass(string fileName         


        

Answer 1

As you can see, myClass is not following a "classic" factory pattern (where the class of the instance is not known/exposed outside the factory).

However in this case, the .NET framework team may not be aiming for a factory pattern, but I guess they do not want you to just new up the target class directly with a filename via a constructor. A factory might be overkill if only this class is being provided.

This pattern is sometimes seen in clone() methods, where an object can return an instance which is a kind of duplicate of itself.

Also maybe although the class is public, they might want to do some checks with the instantiation, filename, etc. and if they implemented a factory, the target class could still be created and invoked, bypassing the checks.