c# - How to change DataTable columns order

Change a DataColumn's Ordinal in DataTable
DataColumnSetOrdinal.aspx

<%@ Page Language="C#" AutoEventWireup="true" %>
<%@ Import Namespace="System.Data" %>

<!DOCTYPE html>
<script runat="server">
    void Button1_Click(object sender, System.EventArgs e)
    {
        DataTable dt = new DataTable();
        dt.TableName = "Books";

        DataColumn dc1 = new DataColumn();
        dc1.ColumnName = "BookID";
        dc1.DataType = typeof(int);
        dc1.AllowDBNull = false;

        DataColumn dc2 = new DataColumn();
        dc2.ColumnName = "BookName";
        dc2.DataType = typeof(string);

        DataColumn dc3 = new DataColumn();
        dc3.ColumnName = "Author";
        dc3.DataType = typeof(string);
        
        dt.Columns.AddRange(new DataColumn[] { dc1,dc2,dc3 });

        dt.Rows.Add(new object[] { 1, "Learning Flash CS4 Professional", "Rich Shupe" });
        dt.Rows.Add(new object[] { 2, "Search Engine Optimization for Flash", "Todd Perkins" });
        dt.Rows.Add(new object[] { 3, "Dreamweaver CS4: The Missing Manual", "David Sawyer McFarland" });
        
        GridView1.DataSource = dt;
        GridView1.DataBind();

        Label1.Text = "<b><u>Columns with Ordinal....</u></b><br />";
        for (int i=0; i< dt.Columns.Count; i++)
        {
            Label1.Text += dt.Columns[i].ColumnName + " || ";
            Label1.Text += dt.Columns[i].Ordinal + "<br/ >";
        }

        dt.Columns[1].SetOrdinal(2);
        Label1.Text += "after Ordinal change......";
        GridView2.DataSource = dt;
        GridView2.DataBind();
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
    <title>Using SetOrdinal() method - How to set change DataColumn Ordinal in DataTable in ado.net</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h2 style="color:DarkBlue; font-style:italic;">
            Using SetOrdinal() method - How to set
            <br /> change DataColumn Ordinal in DataTable in ado.net
        </h2>
        <hr width="525" align="left" color="CornFlowerBlue" />
        <asp:GridView 
            ID="GridView1"
            runat="server"
            BorderColor="Snow"
            ForeColor="Snow"
            Width="550"
            >
            <HeaderStyle BackColor="DarkBlue" Height="35" />
            <RowStyle BackColor="DodgerBlue" />
            <AlternatingRowStyle BackColor="SkyBlue" />
        </asp:GridView>
        <asp:Label
             ID="Label1"
             runat="server"
             Font-Size="Medium"
             ForeColor="HotPink"
             >
        </asp:Label>
        <asp:GridView 
            ID="GridView2"
            runat="server"
            BorderColor="Snow"
            ForeColor="Snow"
            Width="550"
            >
            <HeaderStyle BackColor="DarkBlue" Height="35" />
            <RowStyle BackColor="DodgerBlue" />
            <AlternatingRowStyle BackColor="SkyBlue" />
        </asp:GridView>
        <asp:Button 
            ID="Button1"
            runat="server"
            OnClick="Button1_Click"
            Text="Populate GridView"
            Height="45"
            Font-Bold="true"
            ForeColor="DarkBlue"
            />
    </div>
    </form>
</body>
</html>
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