ExtJs + .NET MVC 不分页处理大数据

刷微博已经成为大家的一种生活方式,我今天要介绍的功能就很类似刷微博。

当我们需要将大数据(比如百万条数据)显示在页面上的时候,显然一次加载是不现实的,用户体验很差。当然,你可能会想到采用分也显示,但是现在的用户已经

厌倦了分页的方式,他们更喜欢刷微博的方式。

于是就出现了这篇文章。

笔者近期的项目中,采用的前端框架是ExtJs,其提供的GridPanel足以应付一次性加载500+以上的记录,只是会让用户等待一会。

但是日志的显示没那么简单,其数据一直在增加,用户也不想分页查看,而是用传统的GridPanel也不太适合。

Google之后,原来ExtJs已经提供了一个插件(Ext.ux.grid.livegrid),强大的Extjs啊!

据说ExtJs 4 提供了一个更加好用的插件来替代这个插件,由于时间关系,笔者仅仅使用了ext 2.2 和 ext 3.3.1两个版本的,效果还不错,

惯例先上图

笔者测试八百万条数据,只需要等待1秒左右,当然那是首次加载的速度。而且我们不是一次加载的。

上代码吧,

这里使用的是Extjs2.2版本,笔者也用了3.3.1的版本,貌似还要简洁很多,但是demo在公司。

Views:

<%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<dynamic>" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Index</title>
    <meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
    <link rel="Stylesheet" type="text/css" href="../../Scripts/Ext/resources/css/ext-all.css" />
    <link rel="Stylesheet" type="text/css" href="../../Scripts/Ext/resources/css/ext-ux-livegrid.css" />
    <link href="../../Content/css.css" rel="stylesheet" type="text/css" />
    <script type="text/javascript" src="../../Scripts/Ext/adapter/ext/ext-base.js"></script>
    <script type="text/javascript" src="../../Scripts/Ext/ext-all.js"></script>
    <script type="text/javascript" src="../../Scripts/Ext/GridPanel.js"></script>
    <script type="text/javascript" src="../../Scripts/Ext/GridView.js"></script>
    <script type="text/javascript" src="../../Scripts/Ext/RowSelectionModel.js"></script>
    <script type="text/javascript" src="../../Scripts/Ext/Store.js"></script>
    <script type="text/javascript" src="../../Scripts/Ext/Toolbar.js"></script>
    <script type="text/javascript" src="../../Scripts/Ext/JsonReader.js"></script>
    <script type="text/javascript" src="../../Scripts/Ext/ext-lang-zh_CN.js"></script>
    <script type="text/javascript" src="../../Scripts/js/grid.js"></script>
    <script src="../../Scripts/js/CHelper.js" type="text/javascript"></script>
    <script type="text/javascript" language="javascript">
        Ext.onReady(function () {
            Ext.BLANK_IMAGE_URL = 'Ext/resources/images/default/tree/s.gif';
            showMe();
        });
    </script>

</head>
<body>
    <div id="content">
   
    </div>
</body>
</html>

Controllers:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using LiveGrid.Models;


namespace LiveGrid.Controllers
{
    public class DefaultController : Controller
    {
        //
        // GET: /Default/

        public ActionResult Index()
        {
            return View();
        }

        #region 获取LiveGrid Data

        /// <summary>
        /// 获取LiveGrid Data
        /// </summary>
        /// <returns></returns>
        public JsonResult GetLiveGridData()
        {
            var starts = null == Request["starts"] ? "0" : Request["starts"];
            var limits = null == Request["limits"] ? "300" : Request["limits"];

            var oLiveGridData = GetLiveData(int.Parse(starts),int.Parse(limits));

            return Json(oLiveGridData,JsonRequestBehavior.AllowGet);
        }

        #endregion

        #region 获取LiveGridData对象

        /// <summary>
        /// 获取LiveGridData对象
        /// </summary>
        /// <param name="starts"></param>
        /// <param name="limits"></param>
        /// <returns></returns>
        public CLiveGridData GetLiveData(int starts, int limits)
        {

            var oLiveGridData = new CLiveGridData();

            //总数据
            var lstData = GetLstData();
            
            //分页数据
            var lstNeedData = GetLstDataByWhere(lstData,starts,limits);

            oLiveGridData.totalCount = lstData.Count;
            oLiveGridData.success = true;
            oLiveGridData.error = string.Empty;
            oLiveGridData.singleInfo = string.Empty;

            var oData = new List<Dictionary<string, string>>();
            foreach(var oPerson in lstNeedData)
            {
                var dicPerson = new Dictionary<string, string>();
                dicPerson.Add("coname", oPerson.coname);
                dicPerson.Add("coarea", oPerson.coarea);
                dicPerson.Add("phonenumber", oPerson.phonenumber);

                oData.Add(dicPerson);
            }

            oLiveGridData.data = oData;

            return oLiveGridData;

        }

        #endregion

        #region 构造数据

        /// <summary>
        /// 构造数据
        /// </summary>
        /// <returns></returns>
        public List<CDataModel> GetLstData()
        {
            var lstData = new List<CDataModel>();

            for (var iIndex = 0; iIndex < 8000000;iIndex++ )
            {
                var oDataModel = new CDataModel();

                oDataModel.coname = string.Format("{0}{1}","LuckyHu",iIndex);
                oDataModel.coarea = "ChengDu";
                oDataModel.phonenumber = "1878028****";

                lstData.Add(oDataModel);
            }

            return lstData;
        }

        #endregion

        #region 获取分页数据

        /// <summary>
        ///  获取分页数据
        /// </summary>
        /// <param name="lstData"></param>
        /// <param name="starts"></param>
        /// <param name="limits"></param>
        /// <returns></returns>
        public List<CDataModel> GetLstDataByWhere(List<CDataModel> lstData, int starts, int limits)
        {
            var lsNeedData = new List<CDataModel>();

            var iMax = starts + limits;
            for (var iIndex = starts; iIndex < iMax;iIndex++ )
            {
                lsNeedData.Add(lstData[iIndex]);
            }

            return lsNeedData;
        }

        #endregion
    }
}

为了适配不同的表结构的数据,笔者设计了一个类,适配该控件

Models:

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

namespace LiveGrid.Models
{
    public class CLiveGridData
    {
        public int totalCount;
        public bool success;
        public string error;
        public string singleInfo;
        //public List<CDataModel> data;
        public List<Dictionary<string, string>> data;
    }

    public class CDataModel
    {
        public string coname;
        public string coarea;
        public string phonenumber;
    }
}

优化的地方还多,呵呵 感谢前辈 OoLaLa 提供的参考

作者: Good_Luck
原文: http://www.cnblogs.com/lucky_hu/archive/2013/06/07/3123172.html