How to randomly select data from one array to another and avoiding duplicate [duplicate]

I am trying to randomly select array values on another array avoiding duplicate but am getting an output that is out of my scope.

please help.

Here is my code below

 static Random rn = new Random();

 static void RandomGenerator()
 {
     String[] greatingsStyles = { "Hello", "Hay", "Morning", "Good day", "Howzit", "Sure" };
     String[] newGreatingsStyles = { };
     for (int j = 0; greatingsStyles.Length >j; j++)
     {
         String ranGreatingsStyles = greatingsStyles[rn.Next(5)];
         if (!greatingsStyles.Contains(ranGreatingsStyles))
         {
             newGreatingsStyles = newGreatingsStyles.Concat(new string[] { ranGreatingsStyles }).ToArray();
         }
     }
     foreach (int i in newGreatingsStyles.ToString())
     {
         Console.WriteLine(i);
     }
}