Load combox2 based on item selected in combox1 from csv

Hi

I am working on a powershell GUI where i have loaded all the server names from a csv file. now each server have multiple services.

Now based on selected servername need to load all the services associated with the selected server from csv file

e.g. data

e.g. data

Host         Description
devas1       check_check_cpu
devas1       check_interface_eth0
devas1       check_interface_eth1
devas1       check_memory
devmart1     check_check_cpu
devmart1     check_interface_eth0
devmart1     check_interface_eth1
devmart1     check_memory
devmart1     check_uptime
devnfs1      mount-check_factorydata
devnfs1      mount-check_home
devnfs1      mount-check_ldmodels
devqcas2     check_cpu
devqcas2     check_interface_eth0
devqcas2     check_interface_eth1
devqcas2     check_memory

Please need some idea on this

Below is the GUI