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);//插入单个元素 
      list.AddRange(new int[] { 1, 2, 3, 4 });//插入一个集合 
 
      //集合转为数组 
      int[] nums = list.ToArray(); 
      foreach (var item in nums) 
      { 
        Console.WriteLine(item); 
      } 
 
      Console.WriteLine(); 
 
      //数组转为集合 
      int[] nums2 = new int[] { 22,33,44}; 
      List<int> newList = nums2.ToList(); 
      foreach (var item in newList) 
      { 
        Console.WriteLine(item); 
      } 
 
      Console.ReadKey(); 
 
    } 
  } 
}