C#用Lambda表達式操作List集合

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.MobileControls;

namespace WebFormTest.TestCollect
{
    public partial class ListOprator : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            People p1 = new People() { Age = 10, Name = "張三", Birth = Convert.ToDateTime("1988-10-1") };
            People p2 = new People() { Age = 18, Name = "張三2", Birth = Convert.ToDateTime("1966-10-2") };
            People p3 = new People() { Age = 12, Name = "張三3", Birth = Convert.ToDateTime("1999-10-3") };
            List<People> list = new List<People>();
            list.Add(p1);
            list.Add(p2);
            list.Add(p3);

            list = list.Select(p => p).ToList(); //獲取所有
            list = list.OrderByDescending(s => s.Age).ToList(); //排序
            list = list.Where(s => (s.Age == 18 || s.Name=="張三3") ).ToList(); //篩選

            foreach (var item in list)
            {
                string str = string.Format("姓名:{0},年齡:{1}，生日:{2}<br />", item.Name, item.Age, item.Birth);
                Response.Write(str);
            }
        }
    }

    class People
    {
        private int age;
        public int Age
        {
            get { return age; }
            set { age = value; }
        }
        private string name;
        public string Name
        {
            get { return name; }
            set { name = value; }
        }
        private DateTime birth;
        public DateTime Birth
        {
            get { return birth; }
            set { birth = value; }
        }
    }
}