为什么自动ID会在10增加，然后在vb.net中不会增加更多

Question

请帮助我和我在vb.net中的子代码 为什么自动ID会在10增加，然后在vb.net中不会增加更多

 Sub autoID(ByVal firstID As String, ByVal tbl As String, ByVal tblID As String, ByVal txt As TextBox)
    connect()
    sql = "SELECT MAX(RIGHT([" & tblID & "],4)) AS id FROM [" & tbl & "]"
    cmd = New SqlCommand(sql, conn)
    reader = cmd.ExecuteReader
    reader.Read()
    If Not reader.HasRows Or IsDBNull(reader.Item("id")) Then
        txt.Text = firstID & "0001"
    Else
        Dim newID As Integer = reader.Item("id")
        newID += 1
        txt.Text = firstID & newID.ToString("0000")
    End If
    conn.Close()
    txt.ReadOnly = True
End Sub