Day
Requirement
What needs to be done
Build a form with a Day Number field and a Show Day button.
When the user clicks Show Day, show the day name: 1 is Monday, 2 is Tuesday, and so on up to 7 which is Sunday. Any other number shows Invalid day number.
Use a Switch: Switch on the day number with one case for each value from 1 to 7, and a default case that handles every other number. Switch is the right choice here because you are matching one value against a fixed list of known options.