C# Public vs private access.

using System;

class MyClass {
  private int alpha; // private access explicitly specified
  int beta;          // private access by default
  public int gamma;  // public access

  /* Methods to access alpha and beta.  It is OK for a member
     of a class to access a private member of the same class. */

  public void SetAlpha(int a) {
    alpha = a;
  }

  public int GetAlpha() {
    return alpha;
  }

  public void SetBeta(int a) {
    beta = a;
  }

  public int GetBeta() {
    return beta;
  }
}
 
class AccessDemo {
  static void Main() {
    MyClass ob = new MyClass();
 
    // Access to alpha and beta is allowed only through methods.
    ob.SetAlpha(-99);
    ob.SetBeta(19);
    Console.WriteLine("ob.alpha is " + ob.GetAlpha());
    Console.WriteLine("ob.beta is " + ob.GetBeta());

    // You cannot access alpha or beta like this:
//  ob.alpha = 10; // Wrong! alpha is private!
//  ob.beta = 9;   // Wrong! beta is private!

    // It is OK to directly access gamma because it is public.
    ob.gamma = 99;
   }
}