Regex to search for everything before a string, and after

Question

I would like to search for everything before the string http://thepaperwall.com/wallpapers/ but not including that string. I would also like to search for everything after .jpg but not including .jpg.

So my final string should look like this:

http://thepaperwall.com/wallpapers/cityscape/small/small_642331afcd78d0840485bb352d99b289b50e8467.jpg

How can I do this?

You want to achieve this with what programming language ? Also, what have you tried so far? Where is your code? — Milche Patern, Dec 15 '13 at 06:56
I'm trying to do this in Yahoo Pipes, I tried ^.*?http://thepaperwall.com/wallpapers/ but that deletes http://thepaperwall.com/wallpapers/ which I don't want it to — user2360087, Dec 15 '13 at 07:06
Go straigth to the yahoo-pipes documentation will help. I found this tuto for you : http://brooksbayne.wordpress.com/2009/01/11/using-regular-expressions-with-yahoo-pipes/ OR http://pipes.yahoo.com/pipes/docs?doc=operators#Regex — Milche Patern, Dec 15 '13 at 07:12
Related : http://stackoverflow.com/questions/2241789/extracting-number-preceding-a-particular-text-using-a-regex — Milche Patern, Dec 15 '13 at 07:21

Szymon · Answer 1 · 2013-12-15T07:03:36.667

2

You can use look-behind and look-ahead to get a string position between 2 other strings:

(?<=http://thepaperwall.com/wallpapers/).*(?=\.jpg)

edited Dec 15 '13 at 07:03

answered Dec 15 '13 at 06:56

Szymon

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How the hell could you figure out OP was about yahoo-pipes regex ? – Milche Patern Dec 15 '13 at 07:09
I want to delete everything before and after those strings – user2360087 Dec 15 '13 at 07:10
Like, how would I search the opposite of that? – user2360087 Dec 15 '13 at 07:19
I didn't figure out, it's a generic regex. What do you mean opposite? – Szymon Dec 15 '13 at 07:36
OK so that expression above matches everything between those 2 strings, I want everything outside of those 2 strings so I can replace them with a blank – user2360087 Dec 15 '13 at 07:47
You changed your question but now it's half way between old and new version. I'm not exactly sure what you want. – Szymon Dec 15 '13 at 07:49
search for text before string but not including string, search for text after string but not including string – user2360087 Dec 15 '13 at 08:06
so if I had this sentence, "Hello, I'm John Marshall" and I want to delete everything before "I'm" but not including "I'm" and I want to delete everything after "John" but not including "John" So I should end up with "I'm John" – user2360087 Dec 15 '13 at 08:09

score 0 · Answer 2 · answered Dec 15 '13 at 07:22

0

You need a non-capturing group:

(.*)(?:http:\/\/thepaperwall\.com\/wallpapers\/.*\.jpg)(.*)

Live demo

answered Dec 15 '13 at 07:22

revo

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Regex to search for everything before a string, and after

2 Answers2