ExtJs + .NET MVC 不分页处理大数据
原帖地址：http://www.cnblogs.com/lucky_hu/archive/2013/06/07/3123172.html
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http://www.cnblogs.com/xuchongyao/archive/2009/11/29/1612886.html
demo下班在弄上去，先上班去了！！！