Production Manager Part Handling

Maybe someone will be able to help me out. I'm working on one software with pc sdk c# application. One of the functions is part selection. All programs will be located on external hd. I'm using the function to read all names of the programs from PartData file to populate a drop-down list inside of my application. The user will select the name of the program and will push the start button. Let's assume user selection will be stored inside of the string partToRun. How can I pass/assign that string to/with Production Manager Part Handling inside of the IRC5 controller? So, when user making selection inside of my application and pushing the button that selection will be set up inside of Production Manager Part Handling and wice wersa - when user will make a selection on flex pendant inside of Production Manager Part Handling on a real controller and will start the robot - user selection from Production Manager Part Handling will show up inside of my application - "this part was selected to run"? I hope it makes sense.
If you need more details ok some pseudo-code let me know.

Thanks for any help or ideas.