Dynamiclly create menu with multiple submenu levels(編號:241)

How to create a mene with the following structure in run time?
MyMenu
--mnuLevel_1[0]
-----mnuLevel_2
..
--mnuLevel_1[j]
-----mnuLevel_2
..

The first level is OK, which can be acheived by defining an array in design time. The problem is in the second level due to the name conflict.