สอบถามเรื่อง การส่งค่าจาก GridView มายัง Textbox รบกวนแนะนำด้วยครับ

   '*** Old ProID ***'
        Dim lblProID As Label = CType(ProductDetailView.FindControl("lblProID"), Label)
        strProID = lblProID.Text
        '*** ProductID ***'
        Dim txtProductID As TextBox = CType(ProductDetailView.FindControl("txtEditProductID"), TextBox)
        '*** ProductName ***'
        Dim txtProductName As TextBox = CType(ProductDetailView.FindControl("txtEditProductName"), TextBox)
        '*** CategoryID ***'
        Dim DropDownListCategory As DropDownList = CType(ProductDatagrid.FindControl("DropDownList1"), DropDownList)
        '*** PromotionID ***'
        Dim DropDownListPromotion As DropDownList = CType(ProductDatagrid.FindControl("DropDownList2"), DropDownList)
        '*** ProductSpec ***'
        Dim txtProductSpec As TextBox = CType(ProductDetailView.FindControl("txtEditProductSpec"), TextBox)
        '*** ProductDesc ***'
        Dim txtProductDesc As TextBox = CType(ProductDetailView.FindControl("txtEditProductDesc"), TextBox)
        '*** Price ***'
        Dim txtPrice As TextBox = CType(ProductDetailView.FindControl("txtEditPrice"), TextBox)
        '*** PromotionPrice ***'
        Dim txtPromotionPrice As TextBox = CType(ProductDetailView.FindControl("txtEditPromotionPrice"), TextBox)
        '*** ImagePath ***'
        Dim txtImagePath As FileUpload = CType(ProductDetailView.FindControl("FileUpload1"), FileUpload)
        '*** ProductRegister ***'
        Dim txtProductRegister As TextBox = CType(ProductDetailView.FindControl("txtEditProductRegister"), TextBox)


        strSQL = "UPDATE Product SET ProductID = '" & txtProductID.Text & "' " & _
            " ,ProductRegister = '" & txtProductRegister.Text & "' " & _
            " ,ProductName = '" & txtProductName.Text & "' " & _
            " ,CategoryID = '" & DropDownListCategory.SelectedValue.ToString & "' " & _
            " ,PromotionID = '" & DropDownListPromotion.SelectedValue.ToString & "' " & _
            " ,ProductSpec = '" & txtProductSpec.Text & "' " & _
            " ,ProductDesc = '" & txtProductDesc.Text & "' " & _
            " ,Price = '" & txtPrice.Text & "' " & _
            " ,PromotionPrice = '" & txtPromotionPrice.Text & "' " & _
            " ,ImagePath = '" & FileUpload1.PostedFile.FileName & "' " & _
            " WHERE ProductID = '" & strProID & "'"

        If Me.FileUpload1.HasFile Then

            Dim intWidth, intHeight As Integer
            Dim UlFileName, NewFileName As String

            intWidth = 100 '*** Fix Width ***'
            'intHeight = 0   '*** If = 0 Auto Re-Cal Size ***'
            intHeight = 120

            UlFileName = "../Images/" & FileUpload1.FileName

            '*** Save Images ***'
            Me.FileUpload1.SaveAs(Server.MapPath(UlFileName))

            NewFileName = "../Images/Thumbnail_" & FileUpload1.FileName


            Dim objGraphic As System.Drawing.Image = System.Drawing.Image.FromFile(Server.MapPath(UlFileName))

            Dim objBitmap As Bitmap
            '*** Calculate Height ***'
            If intHeight > 0 Then
                objBitmap = New Bitmap(objGraphic, intWidth, intHeight)
            Else
                If objGraphic.Width > intWidth Then
                    Dim ratio As Double = objGraphic.Height / objGraphic.Width
                    intHeight = ratio * intWidth
                    objBitmap = New Bitmap(objGraphic, intWidth, intHeight)
                Else
                    objBitmap = New Bitmap(objGraphic)
                End If
            End If

            '*** Save As  ***'
            objBitmap.Save(Server.MapPath(NewFileName), objGraphic.RawFormat)

            '*** Close ***'
            objGraphic.Dispose()
        End If

        sqlcmd = New SqlCommand(strSQL, Conn)
        sqlcmd.ExecuteNonQuery()
        ProductDetailView.ChangeMode(DetailsViewMode.ReadOnly)
        ProductDetailView.Visible = False
        ProductDatagrid.Visible = True
        BindData()