using System; using System.Collections.Generic; using System.IO; using System.Linq; using System.Text; using System.Threading.Tasks;  namespace ConsoleApplication10 {   class Program   {     static void Main(string[] args)     {       List<int> list = new List<int>();       list.Add(1);//插入單個元素       list.AddRange(new int[] { 1, 2, 3, 4 });//插入一個集合        //集合轉為數組       int[] nums = list.ToArray();       foreach (var item in nums)       {         Console.WriteLine(item);       }        Console.WriteLine();        //數組轉為集合       int[] nums2 = new int[] { 22,33,44};       List<int> newList = nums2.ToList();       foreach (var item in newList)       {         Console.WriteLine(item);       }        Console.ReadKey();      }   } }