XojoScript.Input
From Xojo Documentation
Event
The script requests input from the end user with prompt being text to display. Returns a String. You are responsible for creating any UI that prompts the user for data.
Notes
In your script, the Input function calls this event handler. In the event handler you can display your own UI with a prompt for the user to enter data and then return the result (as a string) from the event handler to have it passed back to the script.