regular expressions with escaping round brackets

Question

I am trying to write the expression that will accept the following phone numbers format:

508 736 756
505050505
+48 505 505 505
(+48) 505 505 505
++48 505 505 505
(++48) 505 505 505
(23)692 36 99
23 692 36 99

I wrote the following expression

^(([+]{0,2}?)?([+]{0,2}?)?([0-9 ]+)?)$

However, this expression only covers the formats listed below:

508 736 756
505050505
+48 505 505 505
++48 505 505 505
23 692 36 99

I have an issue with the escaping of the parenthesis characters: (). That's why I can't cover the following formats:

(+48) 505 505 505
(++48) 505 505 505
(23)692 36 99

I tried escaping them with a backslash but it wouldn't work for some reason.

...[(]?[+]{0,2}[)]?...

DEMO: https://regex101.com/r/hY5tG4/2

Answer 1

You can use following regex :

^((\(\+{0,2}[0-9]{1,2}\)|\+{0,2}[0-9]{0,2})?([0-9 ]+)?)$

Demo

Note that you omitted the numbers within parenthesis.Also about the parenthesis and the numbers between them you can not make the brackets optional because the comes together and if you make them optional the regex engine will match some phone numbers like (23692 36 99.

And note this regex will match numbers like (2) 692 36 99 if the length of numbers within brackets must be 2 you can change the renge in regex.