linq to DataTable 排序 

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

namespace ty.net.test.Sort
{
    public partial class WebForm1 : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        DataTable test()
        {
            DataTable dtA = new DataTable();
            dtA.Columns.Add("id", typeof(int));
            dtA.Columns.Add("goodNum", typeof(double));
            dtA.Columns.Add("generalNum", typeof(double));
            dtA.Columns.Add("badNum", typeof(double));

            //dtA.Rows.Add(1, "20", "30", "50");  
            //dtA.Rows.Add(2, "90", "3", "2");  
            dtA.Rows.Add(3, "11", "5", "10");
            dtA.Rows.Add(4, "10", "32", "-2");
            dtA.Rows.Add(5, "66", "55", "44");
            return dtA;
        }

        protected void Button1_Click(object sender, EventArgs e)
        {
            //升序
            DataTable dt = LinqSortDataTable2(test(), "badNum");
            GridView1.DataSource = dt;
            GridView1.DataBind();
        }


        protected void Button2_Click(object sender, EventArgs e)
        {
            //降序
            DataTable dt = LinqSortDataTable(test(), 3);
            GridView1.DataSource = dt;
            GridView1.DataBind();
        }


        /// <summary>
        /// 对datatable按照某一列进行linq排序，因为dataview自带的排序处理不了负数的排序
        /// </summary>
        /// <param name="tmpDt">需要排序的datatable</param>
        /// <param name="sortId">排序的列序号，从0开始</param>
        /// <returns></returns>
        protected DataTable LinqSortDataTable(DataTable tmpDt, int sortId)
        {
            DataView dv = tmpDt.DefaultView;
            var query = (from item in tmpDt.AsEnumerable()
                         orderby Convert.ToInt32(item[sortId]) descending
                         select item);
            //重新排序
            dv = query.AsDataView();
            return dv.ToTable();
        }


        /// <summary>
        /// 对datatable按照某一列进行linq排序
        /// </summary>
        /// <param name="tmpDt">需要排序的datatable</param>
        /// <param name="sortId">排序的列序号，从0开始</param>
        /// <returns></returns>
        protected DataTable LinqSortDataTable2(DataTable tmpDt, string columnName)
        {
            DataView dv = tmpDt.DefaultView;
            var query = (from item in tmpDt.AsEnumerable()
                         orderby item[columnName] 
                         select item);
            //重新排序
            dv = query.AsDataView();
            return dv.ToTable();
        }
    }

}

 

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="ty.net.test.Sort.WebForm1" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:Button ID="Button1" runat="server" Text="升序" OnClick="Button1_Click" />
         <asp:Button ID="Button2" runat="server" Text="降序" OnClick="Button2_Click" />
        <asp:GridView ID="GridView1" runat="server"></asp:GridView>
    </div>
    </form>
</body>
</html>

 

可能你遇到这个问题， AsEnumerable方法找不到？

 

添加引用了System.Data.DataSetExtensions   搞定!!!!

 

posted on 2015-06-01 17:32  广交天下好友  阅读(1137)  评论(0)    收藏  举报

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