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

namespace WebApplication1
{
    public partial class WebForm3 : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        //擴充套件函式和lambda表示式實現查詢。擴充套件函式實現排序。擴充套件函式Skip和Take實現分頁
        protected void Button1_Click(object sender, EventArgs e)
        {
            //Func<UserInfo, bool> whereLambda = u => { return u.ID == 343; };

            EFFristModelEntities db = new EFFristModelEntities();
            //var userInfoList = db.UserInfo.Where<UserInfo>(u=>u.ID==3);  //通過擴充套件函式where和lambda表示式來查詢。<UserInfo>泛型可以省略。

            //升序排序
            //var userInfoList = db.UserInfo.Where<UserInfo>(U => true).OrderBy<UserInfo, int>(u => u.ID);  //根據u.ID排序，int是根據u.ID的型別來判斷的。<泛型>可以省略。
            //降序排序
            //var userInfoList = db.UserInfo.Where<UserInfo>(U => true).OrderByDescending(u => u.ID);  //擴充套件函式OrderByDescending實現降序排序。
            //var userInfoList = db.UserInfo.Where<UserInfo>(U => true).OrderByDescending(u => u.UserPass).ThenByDescending<UserInfo, int>(u => u.ID);//擴充套件函式OrderByDescending,ThenByDescending實現排序。
            
            int pageIndex = 2;
            int pageSize = 2;
            var userInfoList = (from u in db.UserInfo
                                where u.ID > 0
                                orderby u.RegTime ascending, u.ID descending  //linq表示式實現排序。
                                select u).Skip<UserInfo>((pageIndex - 1) * pageSize).Take<UserInfo>(pageSize);  //分頁：Skip:跳過多少條記錄；Take：取幾條記錄。

            foreach (var userInfo in userInfoList)
            {
                Response.Write(userInfo.UserName + "<br/>");
            }
        }
    }
}