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How To Randomize the DataSet Row




<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Randomize.aspx.cs"
Inherits="Randomize" %>


<!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>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:GridView ID="grd" runat="Server"></asp:GridView>
</div>
</form>
</body>
</html>


using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class Randomize : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
grd.DataSource = DataSetUtilities.RandomizeDataTable(CreateDS().Tables[0]);
grd.DataBind();

}
private DataSet CreateDS()
{
DataSet ds;
if (Session["DataList_ParentChild"] == null)
{
ds = new DataSet();
DataTable dt = new DataTable("Company");
DataRow dr;
dt.Columns.Add(new DataColumn("ID", typeof(Int32)));
dt.Columns.Add(new DataColumn("CompanyName", typeof(string)));
dt.Columns.Add(new DataColumn("Address", typeof(string)));
dt.Columns.Add(new DataColumn("Name", typeof(string)));
dt.Columns.Add(new DataColumn("Dept", typeof(string)));
for (int i = 1; i < 10; i++)
{
dr = dt.NewRow();
dr[0] = i;
dr[1] = "Company " + i;
dr[2] = "Address " + i;
dr[3] = "Manager name";
dr[4] = "Adminstration";
dt.Rows.Add(dr);
}
ds.Tables.Add(dt);
DataColumn[] Parent_PKColumns = new DataColumn[1];
Parent_PKColumns[0] = dt.Columns["ID"];
dt.PrimaryKey = Parent_PKColumns;


}
else
{
ds = (DataSet)Session["DataList_ParentChild"];
}
return ds;

}

}
public static class DataSetUtilities
{

static Random _rand = new Random();



public static DataView RandomizeDataTable(DataTable dt)
{

// Create array of indices and populate with ordinal values

int[] indices = new int[dt.Rows.Count];

for (int i = 0; i < indices.Length; i++)

indices[i] = i;



// Knuth-Fisher-Yates shuffle indices randomly

for (int i = indices.Length - 1; i > 0; i--)
{

int n = _rand.Next(i + 1);

int tmp = indices[i];

indices[i] = indices[n];

indices[n] = tmp;

}



// Add new column to data table (if it's not there already)

// to store shuffle index

if (dt.Columns["rndSortId"] == null)

dt.Columns.Add(new DataColumn("rndSortId", typeof(int)));

int rndSortColIdx = dt.Columns["rndSortId"].Ordinal;

for (int i = 0; i < dt.Rows.Count; i++)

dt.Rows[i][rndSortColIdx] = indices[i];



DataView dv = new DataView(dt);

dv.Sort = "rndSortId";

return dv;

}

}

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