Question

How could I write a regex that will match a string containing only question marks

“???” > true

“????” > true

“? ” > true

“?a?” > false

“?a” > false

Thanks in advance !

Edit:
2 cases I missed:

“? ” > true

“?? ? ?” > true

Answer 1

Given that the string can contain spaces (as per the edit), the correct regex is

^[ ?]*[?][ ?]*$

This allows for any number of spaces and question marks and guarantees that at least one question mark is present.