How to create a RegExp to get only integer numbers and no decimals

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Hey guys,

at the moment im going to try to create a RegExp that matchs to integer values in strings.
So i don't have strings like this:
"123" or "123.456"
If that would be the case i could simply use "^[\d]*$" as RegExp.

But like i said, im going to try to get integer values in strings.
Two sample strings could look like this:

A sample integer value is for example 123456 Dollar<br />
Some other decimal value is for example 123.456 Dollar

The goal is, that the RegExp only get a matches the 123456 in the first string and not at 123 or 456 in the second one, because the second string contains a decimal value, not two integer values separated by a dot.

I hope i could make clear what i mean.
If not, feel free to ask.

Thank you so much for your help!

Edit:
I've played with RegExp and found the following two RegExp:
[\d]+(?!\.) all numbers but no number bevore a dot
and
(?<!\.)[\d]+ all numbers but no number after a dot

But i'm confused how to connect them with a logical and operation to get only matches where is no dot bevore a number AND no dot after a number.

Posted 25-Aug-14 23:07pm

C3D1

Updated 26-Aug-14 2:33am

v3

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ChauhanAjay 26-Aug-14 5:49am

try the below link
http://stackoverflow.com/questions/19715303/regex-that-accepts-only-numbers-0-9-and-no-characters

C3D1 26-Aug-14 5:57am

Hey,
in your link they suggest to use "^\d$".
But i think i've made it clear in my question above that something like ^[\d]*$ doesn't work in my (special) case.

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Brian A Stephens · Accepted Answer · 2014-08-26T02:35:00

Solution 1

Here's a regex that will do what you want:

\b(?<!\.)\d+(?!\.\d)\b

\b is a zero-length anchor, matching a "word" boundary. It ensures that the following digits aren't part of a "word" like "abc123".

(?<!\.) is a negative lookbehind that ensures there is no decimal preceding the digits you want

(?!\.\d) is a negative lookahead that ensures there is no decimal and digit following the digits you want

EDIT: added lookbehind to prevent matching part of a decimal

Posted 26-Aug-14 2:35am

Brian A Stephens

Updated 26-Aug-14 2:51am

v4

Comments

C3D1 26-Aug-14 8:44am

Hey,

thank you a lot for your solution.
But i have done a quick look in regex101.com and found, that your regex match to the number after the dot:
http://regex101.com/r/cQ5qB6/2

So it's not exactly what i want, but it's really close to it! :)

Brian A Stephens 26-Aug-14 8:51am

Sorry, I forgot about that stipulation. I've updated it now.

C3D1 26-Aug-14 8:53am

You are a genious :) Thank you so much!