ถ้าไม่มีข้อมูลใน Database AutoNumber ก็ไม่รันให้ ขึ้น Error Input string was not in a correct format.

Public Function KeyStore() As String
        Dim strSQL As String
        Dim int As Integer
        Dim intNum As String = Convert.ToInt32(int)
        Dim sqlCon As New SqlConnection(con)

        'strSQL = "SELECT COUNT(*) FROM Store"
        strSQL = "SELECT replace(max(storeID),'ST','') AS storeID FROM Store"
        Dim cmd As New SqlCommand(strSQL, sqlCon)
        sqlCon.Open()

        If IsDBNull(cmd.ExecuteScalar) Then
            intNum = String.Empty
        Else
            intNum = cmd.ExecuteScalar()
        End If

        intNum += 1

        If int <= 9 Then
            intNum = "ST" & "0" & intNum
        ElseIf int <= 99 Then
            intNum = "ST" & intNum
        End If
        sqlCon.Close()
        Return intNum

    End Function

Protected Sub BuildNoRecord(ByVal ds As DataSet, ByVal gridStore As GridView)
        Try
            If ds.Tables(0).Rows.Count = 0 Then
                ds.Tables(0).Rows.Add(ds.Tables(0).NewRow())
                gridStore.DataSource = ds
                gridStore.DataBind()
                Dim columnCount As Integer = gridStore.Rows(0).Cells.Count
                gridStore.Rows(0).Cells.Clear()
                gridStore.Rows(0).Cells.Add(New TableCell)
                gridStore.Rows(0).Cells(0).ColumnSpan = columnCount
                gridStore.Rows(0).Cells(0).Text = "ไม่พบข้อมูล"
            End If
        Catch ex As Exception

        End Try
    End Sub