下面的代码实现在DataGrid中添加自动编号的功能，主要是在数据绑定时利用Item属性。

查看例子

DataGridWithLine.aspx

<%@ Page Language="vb" AutoEventWireup="false" Codebehind="DataGridWithLine.aspx.vb"
Inherits="aspxWeb.DataGridWithLine"%>

DataGridWithLine.aspx.vb

Imports System
Imports System.Data
Imports System.Data.OleDb
Public Class DataGridWithLine
Inherits System.Web.UI.Page
Protected WithEvents DataGrid1 As System.Web.UI.WebControls.DataGrid

#Region " Web 窗体设计器生成的代码 "

'该调用是 Web 窗体设计器所必需的。
Private Sub InitializeComponent()

End Sub

Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
'CODEGEN: 此方法调用是 Web 窗体设计器所必需的
'不要使用代码编辑器修改它。
InitializeComponent()
End Sub

#End Region

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
DataGrid1.Columns(0).HeaderText = "序号"
DataGrid1.Columns(1).HeaderText = "文章标题"
DataGrid1.Columns(2).HeaderText = "创建日期"
Dim cnString As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Server.MapPath("Test.mdb")
Dim strSQL As String = "SELECT TOP 21 Title,CreateDate FROM Document ORDER By CreateDate DESC"
Dim cn As New OleDbConnection(cnString)
cn.Open()
Dim cmd As New OleDbCommand(strSQL, cn)
Dim db As OleDbDataReader
db = cmd.ExecuteReader(CommandBehavior.CloseConnection)
DataGrid1.DataSource = db
DataGrid1.DataBind()
cn.Close()
cn = Nothing
cmd = Nothing
db.Close()
db = Nothing
End Sub

Private Sub DataGrid1_ItemDataBound(ByVal sender As Object, _
ByVal e As System.Web.UI.WebControls.DataGridItemEventArgs) Handles DataGrid1.ItemDataBound
If e.Item.ItemIndex <> -1 Then
e.Item.Cells(0).Text = e.Item.ItemIndex + 1
End If
End Sub
End Class

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