extract all URLs in a free text block using RegEx

Question

I'm attempting to detect all URLs listed in a free text block. I'm using the .nets Regex.Matches call.. with the following regex: (http|https)://[^\s "']{4,}

Now, I've put in the following text:
here is a link http://somelink.com
here is a link that I didn't space withhttp://nospacelink.com/something?something=&39358235
http://nospacelink.com/something?something=&12233454
here is a link I already handled. Here is some secret t&cs you're not allowed to know https://somethingbad.com
Just to be a little annoying I've put in a new address thingy capture type of 'http://somethinginspeechmarks.com' and what are you going to do now?
here is a link http://postTextLink.com at then some post text
Here is a link with a full stop http://alinkwithafullstoplink.com. And then some more.

and I get the following output:

http://somelink.com
http://nospacelink.com?something=&39358235
http://nospacelink.com?something=&12233454
http://alreadyhandledlink.com
https://somethingbad.com
http://somethinginspeechmarks.com
http://postTextLink.com
http://alinkwithafullstoplink.com.

Please notice the full stop on the last entry. How can I update my regex to say "If there is a full stop at the end, please ignore it?"

Also, please note that "Getting parts of a URL (Regex)" has nothing to do with my question, as that question is about how to break down a particular URL. I want to extract multiple, complete urls. Please see my input and current outputs for clarification! I have got a regex already that does most of what I want, but isn't quite right. Could you please explain where my approach might be improved?

Loving that I can't just mark my own question as duplicate *lol* — Immortal Blue, May 16 '14 at 13:51
Change to `(http|https)://[^\s "']{4,}(?<!\.)` - added `(?<!\.)` in the end. — Ulugbek Umirov, May 16 '14 at 14:05
@Kilazur, I was meaning I could only vote it as a duplicate, as apposed to just closing it as duplicate... — Immortal Blue, May 16 '14 at 14:11
@smerny, could you provide an example of a url which wouldn't pass with (http|https)://[^\s "']{4,}[^\.\s"']+? — Immortal Blue, May 16 '14 at 14:14
@ImmortalBlue, that regex isn't in the answer marked as duplicate — Smern, May 16 '14 at 14:48

kulssaka · Answer 1 · 2014-05-16T14:07:11.390

1

I would add something like [^\.] to the pattern.

This pattern says that the last char can't be a full stop.

So for (http|https)://[^\s "']{4,}[^\.] it will try to match all adresses not ending with a full stop.

Edit:

This one should be better as said in comments: [^.\s"']

edited May 16 '14 at 14:07

answered May 16 '14 at 13:56

kulssaka

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This would actually match `http://alinkwithafullstoplink.com. ` (with an extra space at the end) as well as `http://somethinginspeechmarks.com'` (the quote mark) – Smern May 16 '14 at 13:59
Exact ! then [^\.\s"']+ – kulssaka May 16 '14 at 14:06
User wants dots, just not at the end. – Smern May 16 '14 at 14:17

score -1 · Answer 2 · edited Apr 17 '22 at 09:03

-1

Updated:

Consider the following minor change to your pattern:

(http|https)://[^\s "']{4,}(?=\.)

edited Apr 17 '22 at 09:03

halfer

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answered May 16 '14 at 14:04

gpmurthy

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that stops at any ., so gives the output of `http://somelink` and `http://nospacelink` etc... – Immortal Blue May 16 '14 at 14:13
Fixed the pattern. Try that for size. – gpmurthy May 16 '14 at 14:35
That still returns the . at the end... `http://linkwithafullstop.com.` `http://alinkwithafullstoplink.com.` – Immortal Blue May 16 '14 at 15:04
Made a minor change to the pattern... . to \. – gpmurthy May 16 '14 at 15:16

extract all URLs in a free text block using RegEx

2 Answers2