How to match one number in url with regex

Question

I have this URL and I only want to match 4 which can be any number from 0-99.

/img/4.png?t=1351606887

What's the regex to match the number 4 and any other number only?

Do you want to match the number 4 only if it appears before .png? Or is it okay if find the number 4 after t=? — Blaise Swanwick
– Blaise Swanwick, Commented Oct 30, 2012 at 18:58

Martin Ender · Accepted Answer · 2012-10-30 18:58:23Z

1

This really depends on how flexible your URL can be. Depending on your regex flavor you can either use lookarounds:

(?<=/img/)\d+(?=\.png)

Or a capturing group:

/img/(\d+)\.png

In the latter case you will match /img/4.png but the first captured group will contain only the 4.

Which variant you can use, and how to retrieve the capture content really depends on your language/tool.

answered Oct 30, 2012 at 18:58

Martin Ender

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3 Comments

Damn it @m.buettner! Can't get a word in when you're online :D

@acheong87 sorry about that :D

is this javascript? javascript doesn't support lookbehinds (the (?<=...) thing). Use the second version instead.

tink · Accepted Answer · 2012-10-30 18:59:19Z

0

/\/[0-9]+/

Will that suffice, you think?

answered Oct 30, 2012 at 18:59

tink

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