I read this kind of questions multiple times on the ASP.NET forums. Most of the time it's suggested that one can use one of the events of the grid control they're using to use the FindControl method to find a Label control in one of the template columns and add the current row number to its Text property. I also used to do it like that when I started with ASP.NET.
However it can be done easier, and in markup, without the use of events, and best of all, the grid controls(1) of ASP.NET support the technique.
Figure 1: The GridView, DataGrid, Repeater and DataList controls shown to present the technique.
If Figure 1 you can see that it also supports pagination, which is shown in the GridView control.
Code says more than words so here goes:
1 <%@ Page Language="C#" %>
2
3 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
4
5 <script runat="server">
6
7 protected void DataGrid1_PageIndexChanged(object source, DataGridPageChangedEventArgs e)
8 {
9 DataGrid1.CurrentPageIndex = e.NewPageIndex;
10 DataGrid1.DataBind();
11 }
12 </script>
13
14 <html xmlns="http://www.w3.org/1999/xhtml" >
15 <head runat="server">
16 <title>Autonumbering grid controls</title>
17 </head>
18 <body>
19 <form id="form1" runat="server">
20 <div>
21 GridView</div>
22 <asp:GridView ID="GridView1" runat="server" AllowPaging="True" AllowSorting="True"
23 AutoGenerateColumns="False" DataSourceID="SqlDataSource1" PageSize="5">
24 <Columns>
25 <asp:TemplateField>
26 <ItemTemplate>
27 <%# Container.DataItemIndex + 1 %>
28 </ItemTemplate>
29 </asp:TemplateField>
30 <asp:BoundField DataField="CategoryName" HeaderText="CategoryName" SortExpression="CategoryName" />
31 <asp:BoundField DataField="Description" HeaderText="Description" SortExpression="Description" />
32 </Columns>
33 </asp:GridView>
34 <br />
35 DataGrid
36 <br />
37 <asp:DataGrid runat="server" ID="DataGrid1" DataSourceID="SqlDataSource1" AllowPaging="True" OnPageIndexChanged="DataGrid1_PageIndexChanged" PageSize="5">
38 <Columns>
39 <asp:TemplateColumn>
40 <ItemTemplate>
41 <%# Container.DataSetIndex + 1 %>
42 </ItemTemplate>
43 </asp:TemplateColumn>
44 </Columns>
45 </asp:DataGrid><br />
46 Repeater<br />
47 <asp:Repeater ID="Repeater1" runat="server" DataSourceID="SqlDataSource1">
48 <ItemTemplate>
49 <span style="margin-right:20px;"><%# Container.ItemIndex + 1 %></span>
50 <span><%# Eval("CategoryName") %> <%# Eval("Description") %></span><br />
51 </ItemTemplate>
52 </asp:Repeater><br />
53 DataList
54 <br />
55 <asp:DataList ID="DataList1" runat="server" DataSourceID="SqlDataSource1">
56 <ItemTemplate>
57 <%# Container.ItemIndex + 1 %>
58 CategoryName:
59 <asp:Label ID="CategoryNameLabel" runat="server" Text='<%# Eval("CategoryName") %>'>
60 </asp:Label><br />
61 Description:
62 <asp:Label ID="DescriptionLabel" runat="server" Text='<%# Eval("Description") %>'>
63 </asp:Label><br />
64 <br />
65 </ItemTemplate>
66 </asp:DataList>
67 <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>"
68 SelectCommand="SELECT [CategoryName], [Description] FROM [Categories]"></asp:SqlDataSource>
69 </form>
70 </body>
71 </html>
For simplicity I used the SqlDataSource control that ships with ASP.NET 2.0 and used the Northwind database (lines 67 - 68). The following lines are of importance: 27, 41, 49 and 57. The + 1 is added each time because of the zero based index.
As you can see, it's each time a very simple addition to the markup of the grid control you're using but it adds that nice extra touch of information that endusers like to see.
Grz, Kris.
(1): I tested it upon the GridView, DataGrid, DataList and Repeater controls.
