Private Sub listCard(ByVal PNO As String)
       Dim connectString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
                                     "Data Source=|DataDirectory|AWingAMS.mdb"
        Using conn as new OleDbConnection(connectString)
            Using cmd As New OleDbCommand("SELECT [PNO], [Name], [school] FROM [PersData] where PNo=@PNO", con)
            cmd.Parameters.AddWithValue("@PNO", PNO)
            cmd.CommandType = Data.CommandType.Text 'This is the Default value, so you can skip this line
               Try
                  con.Open()
                  Using rdr = cmd.ExecuteReader()
                      If rdr.Read() Then
                          pnotxt.Text = rdr.Item("PNO")
                          nametxt.Text = rdr.Item("Name")
                          schooltxt.Text = rdr.Item("school")
                      End If
                      rdr.Close
                  End Using
                Catch ex As Exception
                    Response.Write(Err.Description)
                Finally
                    con.Close()
                End Try
            End Using
        End Using
    End Sub