regex to extract the number from string

Question

I have a string like this

file-myfle_20130207_094852am.csv

how do i go about writing the regex to extract only the numbers

20130207094852

What kind of tool are you using? What are you actually trying to do? (file renaming?) — nhahtdh
– nhahtdh, Commented Feb 7, 2013 at 4:37
Your question doesn't make a lot of sense. Regular expressions don't "extract" anything, they match patterns. If you want to transform your input string to the desired output string, that's a somewhat different thing to do. — David M
– David M, Commented Feb 7, 2013 at 4:55

Simon Whitehead · Accepted Answer · 2013-02-07 04:22:43Z

5

Like this (this is pretty common among Regex tutorials)

\d+

Each group will be the numbers.

answered Feb 7, 2013 at 4:22

Simon Whitehead

65.3k10 gold badges120 silver badges140 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

Might want to use * to account for the lack of numbers.

@AshwinMukhija, no. No number is not a number (which was of interest). Off topic, +5 for \d+, fu SO... ;-)

This is at best incomplete solution. The numbers in the question are separated by _.

@nhahtdh Without a known language to combine them back together.. how do you propose I update my answer?

@SimonWhitehead: That's why I just leave a plain comment. I am curious why no one even ask the OP to include more information.

David M · Accepted Answer · 2013-02-07 05:01:35Z

0

See my comment on the question for context.

From a shell:

echo file-myfle_20130207_094852am.csv | tr -cd /0-9/
20130207094852

With Perl:

echo file-myfle_20130207_094852am.csv | perl -pe 's/\D//g'
20130207094852

answered Feb 7, 2013 at 5:01

David M

4,3962 gold badges32 silver badges40 bronze badges