matching value of html src attribute

I need to get the top level domain from the request header but it can be in a vary ways.. how can I match but exclude parts I dont want to get ie. ports

Eliminate spaces in the inner part of parenthesis.

Validates most email addresses. Using the range [A-Za-z0-9] at the beginning instead of \w means an address cannot begin with an underscore. This range is also used to exclude underscores from the domain (part after @).

States (US) 2 char format, matches: Ga or GA

Validador de CPF

Match Wikipedia anchor dot-instead-of-percent encoding string.replace(/((?:\.[a-f0-9]{2}){2})/ig, function(match) { return decodeURIComponent(match.replace(/\./g, '%')) });

Pattern that check your string to match Google Plus user profile URL.

this regular expression allow numbers with one number from 1 to 5 and only one decimal value Onlys accept numeric values from 1.0 to 5

little matcher for french phone number in locale format (example: 0231348228)

Fully qualified domain name validation

Get all strings in vb.net format (even nested quotes"