Regular expression for finding currency values but not dates in text

Question

I have text like the following two example strings

this book was sold for 12.00 on 12.12.2010
he paid 12.12.2010 , and puchased an amount of 15.00

Answer 1

You could use

\d+\.\d{2}(?![.\d])

if all you need is to distinguish between dates in exactly this format and currency amounts in exactly this format.

This regex looks for the pattern digits, dot, two-digits but only if it's not followed by either another dot or another digit (to prevent the dates from matching).

Quick PowerShell test:

Update for short dates in the form dd.mm.yy (just in case you need them):

(?<![.\d])\d+\.\d{2}(?![.\d])

Answer 2

Try this

\b\d+\.\d{2}(?!\.?\d)

See it here on Regexr

\b is a word boundary, this ensures that there is a non word character (includes also digits) before the first digit.

\d+\.\d{2} is at least one digit, followed by a dot and two other digits.

(?!\.?\d) is a negative look ahead that ensures that there is no digit OR no dot followed by a digit ahead. This would allow the amount to be at the end of the sentence.

Working c# code:

String s = "this book was sold for 12.00 on 12.12.2010";

Regex r = new Regex(@"\b\d+\.\d{2}(?!\.?\d)");

Console.WriteLine(r.Matches(s)[0]);
Console.ReadLine();

Answer 3

Try this one:

(?:\s|^)\d+\.\d+(?:\s|$)

It gives two matches in my test:

12.00 
15.00