dynamic table and button creation in asp.net - vb.net

Question

I have created a dynamic table using for loop condition.In which it has a button while i click a specific button it should open a file.But in my coding it is opening a file button in the last row.
If Not IsPostBack Then
txtlogsdate.Text = FormatDate(Now)
End If
Try
trViewlogs.Visible = True
lbllogs.Visible = False
lbllogname.Visible = True
RT1.Visible = False
pb.Visible = False
Dim d1 As DateTime = txtlogsdate.Text
Dim dd As String = d1.ToString("dd")
Dim mm As String = d1.ToString("MM")
Dim yy As String = d1.ToString("yy")
Dim d2 As String = yy & "" & mm & "" & dd
Dim di As DirectoryInfo = New DirectoryInfo(Server.MapPath("~\logs"))
Dim files As FileInfo() = di.GetFiles("*.log")
Dim tab As New Table()
tab.CellPadding = 0
tab.CellSpacing = 0
tab.BorderStyle = BorderStyle.Double
tab.Attributes.Add("style", "margin-left: 0.5px; width: 800px;")
Dim row As New TableRow()
Dim headerCell1 As New TableHeaderCell()
headerCell1.Text = "Logs"
headerCell1.Attributes.Add("style", "margin-left: 0.5px; height: 20px;")
headerCell1.BackColor = System.Drawing.Color.CornflowerBlue
headerCell1.ForeColor = System.Drawing.Color.White
row.Controls.Add(headerCell1)
tab.Controls.Add(row)
Dim headerCell2 = New TableHeaderCell()
headerCell2.Attributes.Add("style", "margin-left: 0.5px; height: 20px;")
headerCell2.BackColor = System.Drawing.Color.CornflowerBlue
headerCell2.ForeColor = System.Drawing.Color.White
headerCell2.Text = "Download"
row.Controls.Add(headerCell2)
tab.Controls.Add(row)
For i As Integer = 0 To files.Length - 1
Dim a As String = files(i).ToString.Replace("Event-", "")
Dim c As String = a.Substring(0, 6)
Dim sw As String
If d2 = c Then
sw = My.Computer.FileSystem.ReadAllText(_
GetWebSitePhysicalRoot & "\logs\" & files(i).ToString)
lbllogname.Text = files(i).ToString
lbllogname.Visible = False
row = New TableRow()
If i Mod 2 = 0 Then
row.BackColor = System.Drawing.Color.White
Else
row.BackColor = System.Drawing.Color.AliceBlue
End If
Dim cell As New TableCell()
cell.Text = lbllogname.Text
'cell.Width = New Unit("1000px")
cell.HorizontalAlign = HorizontalAlign.Center
row.Controls.Add(cell)
Dim cell2 As New TableCell()
Dim bt As New Button
bt.BorderStyle = BorderStyle.Solid
bt.Text = files(i).ToString
AddHandler bt.Click, AddressOf bt_Click
cell2.HorizontalAlign = HorizontalAlign.Center
cell2.Controls.Add(bt)
row.Controls.Add(cell2)
tab.Controls.Add(row)
Panel1.Controls.Add(tab)
End If
Next i
If lbllogname.Text = "" Then
lbllogname.Text = "No Logs to Display !"
End If
Session("pageurl") = ""
Session("pagecount") = ""
ib.SetInfo("Reports > View Logs", Infobar.InfoTypes.Caption)
Dim mi As Integer = GetQueryStringToInt("menuindex", 1)
If Not IsPostBack Then
leftmenu1.AddItem("View Logs", _
GetWebSiteUrlRoot & "/staff_rpt.aspx?rpt=logs&page=1&menuindex=" & mi)
End If
Catch ex As Exception
WriteLog(LogWriter.EventType.eError, ex.StackTrace.ToString)
End Try
Protected Sub bt_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs
Dim a As String
a = lbllogname.Text
Response.ContentType = "text/plain"
Response.AppendHeader("Content-Disposition", "attachment; filename=" & a)
Response.TransmitFile(Server.MapPath("~/logs/" & a))
Response.End()
End Sub

Answer 1

To use the dynamic table structure you have built in your code, then you need to uniquely name each button in each row; otherwise the button click handler (bt_Click) cannot figure out the correct row to open the file in, because they are all called the same and will use the last one.
Since you want a table structure, then I suggest you use the GridView server control, as it will provide similar output, but provide the ability to use templating to name the controls of each row the same, but allow for you to differentiate individual rows when a click event happens.