datalist updae coding in vb.net

Protected Sub DataList1_UpdateCommand(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataListCommandEventArgs) Handles DataList1.UpdateCommand
        Dim AgentId As String = DataList1.DataKeys(e.Item.ItemIndex).ToString()
        DataList1.DataKeys(e.Item.ItemIndex).ToString()
        Dim Name As TextBox = CType(e.Item.FindControl("txtName"), TextBox)
        str = ""
        Try
            openConnection(con)
            
            str = "UPDATE Agent_Master SET A_Name='" & Name.Text & "'WHERE AgentId ='" & AgentId & "'"

            cmd = New OleDbCommand(str, con)

            cmd.ExecuteNonQuery()

            LoadData()
            DataList1.EditItemIndex = -1

        Catch ex As Exception
            alert(MessageType.Fail)
        Finally
            con.Close()
        End Try
        
    End Sub