ASP .net validation of phone number

f.e.:+420 333 222 111

Pattern: /^(\+[0-9]{0,3})*( ([0-9]{0,3})){3}$/

Finds U.S. phone numbers with extensions.
Pattern: /(\+?1[-\.\/ ])?(\(?\d{3}\)?[ \.\-\/]?)?(\d{3})[\-\.\/ ]([\d]{4}|[A-Z]{7})(\(\d{4}\))?(( )?(ext\.)|(x\.?)? ?\d{4})?(([ ,\/] ?\d{4})?)+/g

morocco phone number like this one :+21260010101or 0021260010101the code will find the both number it's my first code here :))
Pattern: (\+|00)(212)\d{8}

Phone Number   Extension (allows (), ., -, and space)

/^\(?([0-9]{3})\)?\s*[\. -]?\s*([0-9]{3})\s*[\. -]?\s*([0-9]{4})\s?((ext|x)\s*\.?:?\s*([0-9]+))?$/i

Phone number india
^([+][9][1]|[9][1]|[0]){0,1}([7-9]{1})([0-9]{9})$

Pattern: /^[0-9]{0,5}[ ]{0,1}[0-9]{0,6}$/g