youtube-nullcoalescing-c#8

Program.cs

  class Program
  {
      static void Main(string[] args)
      {
          static int? GetNullAge() => null;
          static int? GetAge() => 27;

          int? age = GetNullAge();

          //Old Way
          //if (age == null)
          //{
          //    age = GetAge();
          //}

          //C# 7
          //age = age ?? GetAge();

          //C# 8.0
          age ??= GetAge();

          Console.WriteLine(age);
          Console.ReadLine();
      }
  }