Use a static constructor. : static field « Class « C# / CSharp Tutorial

1. C# / CSharp Tutorial
2. Class
3. static field

using System; 
 
class Cons { 
  public static int a; 
  public int b; 
 
  // static constructor 
  static Cons() { 
    a = 99; 
    Console.WriteLine("Inside static constructor."); 
  } 
 
  // instance constructor 
  public Cons() { 
    b = 100; 
    Console.WriteLine("Inside instance constructor."); 
  } 
} 
  
class MainClass { 
  public static void Main() {   
    Cons ob = new Cons(); 
 
    Console.WriteLine("Cons.a: " + Cons.a); 
    Console.WriteLine("ob.b: " + ob.b); 
  } 
}

Inside static constructor.
Inside instance constructor.
Cons.a: 99
ob.b: 100