need help on Enumerations

namespace EnumExample
{
    class Program
    {
        public enum TimeOfDay
        {
            Morning = 0,
            Afternoon = 1,
            Evening = 2
        }
        static int Main(string[] args)
        {
            WriteGreeting(TimeOfDay.Morning);
            return 0;
        }
        static void WriteGreeting(TimeOfDay timeOfDay)
        {
            // the output through switch case is "Good morning!"
             switch(timeOfDay)
             {
                 case TimeOfDay.Morning:
                     Console.WriteLine("Good morning!");
                     break;
                 case TimeOfDay.Afternoon:
                     Console.WriteLine("Good afternoon!");
                     break;
                 case TimeOfDay.Evening:
                     Console.WriteLine("Good evening!");
                     break;
                 default:
                     Console.WriteLine("Hello!");
                     break;
             }
            
            // the output for following two lines is "Afternoon"
           
             TimeOfDay time = TimeOfDay.Afternoon;
             Console.WriteLine(time.ToString());            // ToString() method is used
            
            // the output of following two lines also "Afternoon"
           
             TimeOfDay time3 = TimeOfDay.Afternoon;
             Console.WriteLine(time3);                      // the same output is coming even the ToString() method was not used


            //=============================================================
            
                     
   // the output for following two lines is "2"
            
    TimeOfDay time2 = (TimeOfDay)Enum.Parse(typeof(TimeOfDay), "evening", true); // Enum.Parse method is used
             Console.WriteLine((int)time2);
          
 // the output of following two lines also "2"
          
  TimeOfDay time4 = TimeOfDay.Evening; // the same output is coming even the Enum.Parse method was not used
       
   Console.WriteLine((int)time4);



        }

    }
}