How to match whole word that is preceded by a tab?

Question

I am trying to get the first word in the line that matches the whole word 'number'. But I am only interested where whole word 'number' is matched and is preceded by a tab.

For example if following is the text:

tin identification number 4/10/2007 LB
num number 9/27/2006 PAT

I want to get back num

Regex I have is:

match whole word: \bnumber\b

if above is found then get first word: ([^\s]*)

I think I need modification in match whole word regex so that it only matches when whole word is preceded by a tab

Answer 1

This answer depends a bit on your regex engine as they can have different representations for tab. In the .Net regex engine though it would look like ...

\tnumber

Answer 2

(?:(\t([^\t ]*)))

Answer 3

try lookahead:

([^\s]+)(?=.*\tnumber)