List遍历删除 或取指定的前N项

    class Program
    {
        static void Main(string[] args)
        {
            /*
             * List遍历删除 或取指定的前N项
            */
            List<PerSon> listPer = CreateListPer();

            // 1、输出项
            Console.WriteLine("输出listPer项");
            foreach (PerSon per in listPer)
            {
                Console.WriteLine("Id:" + per.Id + " Name:" + per.name);
            }

            //2、删除15条之后的数据
            //遍历删除索引大于50的项
            //将listPer的项复制到listPerTemp里面 如果直接用“=”的话，listPerTemp删除索引大于15的项，listPer大于15的项也会删掉
            List<PerSon> listPerTemp = new List<PerSon>(listPer.ToArray());
            //这将复制listPer中的所有项目到listPerTemp 
            //listPer.ForEach（i => listPerTemp.Add（i）); 
            listPer.ForEach(i => listPerTemp.Add(i));
            for (int i = listPerTemp.Count - 1; i >= 0; i--)
            {
                if (i >= 15)
                {
                    listPerTemp.RemoveAt(i);
                }
            }
            Console.Write("
");
            // 3、输出项
            Console.WriteLine("输出listPerTemp项");
            foreach (PerSon per in listPerTemp)
            {
                Console.WriteLine("Id:" + per.Id + " Name:" + per.name);
            }

            //
            Console.Write("
");
            Console.WriteLine("输出listPer项");
            foreach (PerSon per in listPer)
            {
                Console.WriteLine("Id:" + per.Id + " Name:" + per.name);
            }

            Console.Write("
");
            //除了用移除的方法获取索引小于15的项，还可以用.take(15);  
            var result = from r in listPer
                         select r;

            result = result.Take(15);
            foreach (var c in result)
            {
                Console.WriteLine("Id:" + c.Id + " Name:" + c.name);
            }

            Console.Write("
");
           //或者直接take
            listPer = listPer.Take(15).ToList();
            foreach (PerSon per in listPer)
            {
                Console.WriteLine("Id:" + per.Id + " Name:" + per.name);
            }
            Console.ReadKey();
        }

        private static List<PerSon> CreateListPer()
        {
            List<PerSon> listper = new List<PerSon>();
            PerSon per = new PerSon();
            for (int i = 1; i <= 20; i++)
            {
                per = new PerSon();
                per.Id = i;
                per.name = "N-" + i;
                listper.Add(per);
            }

            return listper;
        }
    }

    public class PerSon
    {
        /// <summary>
        /// 编号
        /// </summary>
        public int Id { get; set; }

        /// <summary>
        /// 名称
        /// </summary>
        public string name { get; set; }
    }