Regex for taking only the domain name

Question

I have this list of domains

https://download.my-domain.com/auth/login
https://download.my-domain.com
http://localhost:60162/API/script/authbar.js
http://localhost:28173/logout.aspx
http://my-domain.com/logout.aspx
http://my-domain.com/logout.aspx/
http://my-domain.com/
http://my-domain.com
http://my-domain.tk/
http://my-domain.gov
download.my-domain.com/auth/login
www.download.my-domain.com/auth/login
http://www.google.com
https://www.google.com
http://www.google.com/
https://www.google.com/

and i tried

((\.)?[a-zA-Z0-9-]+\.([a-zA-Z0-9]{2,4}))/?

but it also detects the logout.aspx any help would be appreciated..

TYIA

Expected Result:

my-domain.com

localhost (without the port)

google.com

my-domain.tk

my-domain.gov

Usage:

For cookie domain

Ulugbek Umirov · Accepted Answer · 2014-05-13T05:52:32.610

1

The following might work for you:

[-a-z0-9_]+(?!://)(?:\.[-a-z0-9_]+)?(?=[/:]|$)

Regular expression visualization

JS Demo

C# Demo

edited May 13 '14 at 05:52

answered May 13 '14 at 03:57

Ulugbek Umirov

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yeah.. it does work but it includes the subdomain.. amazing.. it has a graph.. how did you generate it anyway if its ok if i ask? :) – Vincent Dagpin May 13 '14 at 03:59
@VincentDagpin Sorry, missed that point, just a moment. – Ulugbek Umirov May 13 '14 at 03:59
@VincentDagpin The image is generated by https://debuggex.com/ – Ulugbek Umirov May 13 '14 at 05:53

score 1 · Answer 2 · answered May 13 '14 at 04:00

1

maybe this one is more likely to work in your example

([a-zA-Z0-9-]+(\.(com|net|org|info|coop|co\.uk|org\.uk|ac\.uk|uk|tk|gov)))|localhost

answered May 13 '14 at 04:00

Zhen Zhang

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score 1 · Answer 3 · answered May 13 '14 at 04:29

I did this with minimum regular expression in Javascript because I was bored. I imagine it would be pretty easy to convert to c#?

var urls = [
  'https://download.my-domain.com/auth/login',
  'https://download.my-domain.com',
  'http://localhost:60162/API/script/authbar.js',
  'http://localhost:28173/logout.aspx',
  'http://my-domain.com/logout.aspx',
  'http://my-domain.com/logout.aspx/',
  'http://my-domain.com/',
  'http://my-domain.com',
  'http://my-domain.tk/',
  'http://my-domain.gov',
  'download.my-domain.com/auth/login',
  'www.download.my-domain.com/auth/login',
  'http://www.google.com',
  'https://www.google.com',
  'http://www.google.com/',
  'https://www.google.com/'
];

var domains = urls.map(function (url) {
  var domain = url.replace(/^https?:\/\//, '').split('/')[0];

  if (domain.indexOf(':') > 0) {
    domain = domain.split(':')[0];
  } else {
    domain = domain.split('.').slice(-2).join('.');
  }

  return domain;
});

i added some syntax in C# from your answer. i cant add it in comment because it's too long.. :) — Vincent Dagpin, May 13 '14 at 04:48

score 0 · Answer 4 · answered May 13 '14 at 03:52

0

Instead of

((\.)?[a-zA-Z0-9-]+\.([a-zA-Z0-9]{2,4}))/?

You should add all possible top level domain

((\.)?[a-zA-Z0-9-]+\.(com|net|org|info|coop|co\.uk|org\.uk|ac\.uk|uk|tk)/?

answered May 13 '14 at 03:52

coder hacker

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score 0 · Answer 5 · answered May 13 '14 at 04:01

Try this:

Regex("^(?>https?://|)([-A-Z0-9+&@#%?=~_|!,.;]+)", RegexOptions.IgnoreCase);

if you want to ignore lines ending in logout.aspx, then try the following:

Regex("^(?>https?://|)([-A-Z0-9+&@#%?=~_|!,.;]+)[-A-Z0-9+&@#%?=~_|!,:/.;]*(?<!logout.aspx/?)$", RegexOptions.IgnoreCase);

Regex for taking only the domain name

5 Answers5