Hi Clay,

Thank you so much for your reply.

Our InfoPath form is a standalone form which doesn't access Web Service or
Database.

I saw some code on internet to demo on populating dynamic dropdown on Form
Load event handler. But my form need to fiter data on dropdown list on
Command event handler.

InfoPath has build-in support to filter data on dropdown list. But we need
to achieve it by using code behind as InfoPath build-in filter data support
is not good enough for our case.

So is there nayway that could filter data on dropdownlist by using code
behind?  

Many thanks,

Forrest