OnPress and unknown commands

[Mayve]

Hello, I am wondering if OnPress can be used with unknown commands?

Specifically, I would like to achieve the result of typing "/act end" only through OnPress.

When I try it, it doesn't work. I even made a txt file with just "act end" and tried OnPress="do_file_commands (txt file)" and that didn't work as well. I added a line to the txt file to make it write "test" in chat and tried it again and get the word test displayed but not the "Unknown command: act end" that is usually displayed by typing "/act end" or pressing the macro on my hotbar that types it for me.

Any solutions or ideas how to get this to work or is not possible since it's not a real command?