Why we have to declare static member function to access private static variable? Why not simply use a public function to access s_nValue? I mean why is it better to use static member function instead of a non-static public function?
class Something { private: static int s_nValue; }; int Something::s_nValue = 1; // initializer int main() { } Why we have to declare static member function to access private static variable?
You don't have to:
class Something { private: static int s_nValue; public: static int staticAccess() { return s_nValue; } int Access() { return s_nValue; } }; int Something::s_nValue = 1; // initializer int main() { Something s; Something::staticAccess(); s.Access(); return 0; } Both methods work as can bee seen here
That being said, it doesn't really make sense to make a non-static member function to access a static variable (as you would need an instance of the class to be able to call it).
If you use pubilc function , you have to call it using an object, and it's not appropriate to call a static function with object, so better to keep it in static method which can be accessible directly through "classname::"
Why we have to declare static member function to access private static variable?
You don't have to. You can access a private static member from any member function, static or otherwise. You can also access it from any friend function, or member function of a friend class.
Why not simply use a public function to access s_nValue?
Because that's less simple than a static function. You need an object to call a non-static member function; why not simply allow access to the static variable without creating an object?
TypeName::Methodname();