Simple implementation of GridView sorting

using System;
using ;
using ;
using ;
using ;
using ;
using ;
using ;
using ;
using ;

public partial class GridViewSort :
{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
ViewState["SortOrder"] = "PID";
ViewState["OrderDire"] = "Desc";
Bind();
}
}
private void Bind()
{
= true;
DataView dv = getDt().DefaultView;
= (string)ViewState["SortOrder"] + " " + (string)ViewState["OrderDire"];
= dv;
();
}
/// <summary>
/// Even if you have trouble with the database, directly construct a DataTable
/// </summary>
/// <returns></returns>
private DataTable getDt()
{
DataTable dt = new DataTable();
("PID", typeof(System.Int32));
("UserName", typeof());
for (int i = 0; i < 10; i++)
{
DataRow dr = ();
dr["PID"] = i;
dr["UserName"] = "Name" + i;
(dr);
}
return dt;
}
protected void gdvSort_Sorting(object sender, GridViewSortEventArgs e)
{
string sPage = ;
if (ViewState["SortOrder"].ToString() == sPage)
{
if (ViewState["OrderDire"].ToString() == "Desc")
{
ViewState["OrderDire"] = "Asc";
}
else
{
ViewState["OrderDire"] = "Desc";
}
}
else
ViewState["SortOrder"] = ;
Bind();
}
}