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!!!!
