relationship between private constructor and derivation class

Question

which relationship between private constructor and derivation class that derivation is not possible
(meaning constructor implements the actions required to initialize an instance)
mean - stop create instance ok, but derive class ?

Mahesh Chand · Answer

You can not use private constructor to create an instance of the class even in derived classes. If you want to access a constructor in derived classes but not in others, you have to make constructor as protected. To create an instance of a class using private constructor is through a public method. The public method internally calls the private constructor and returns the instance of the class.

Krishnaraj L · Answer

Hi there, You normally use private constructors for singleton implementation. That means you will not be able to create an object like this A oA = new A(); Well now for creating an object which has a private constructor, you need to expose static method to create it and maintain a single instance. Please search for singleton implementation in google. And for preventing a class being inherited use sealed keyword. sealed class A { public int i; } if you try to derive a class from this, you will get an error. Hope this helps!!!

relationship between private constructor and derivation class

Answers (2)