I found this code in some website, and it works perfectly. It validates that the phone number is in one of these formats: (123) 456-7890 or 123-
My regex of choice is:
/^[\+]?[(]?[0-9]{3}[)]?[-\s\.]?[0-9]{3}[-\s\.]?[0-9]{4,6}$/im
Valid formats:
(123) 456-7890 (123)456-7890 123-456-7890 123.456.7890 1234567890 +31636363634 075-63546725