Powershell Regular Expression to extract string between rounded parentheses from line in a log file

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This is a line in a log file:

$line = 'to devices Headset Earphone (Some Device)'

I need the result done with an one liner regex only (if possible):

$result = 'Some Device'

I have it working in two lines:

$InsideLoopLine = [regex]::Matches($Line, '^.*to devices Headset.*$')
                  [regex]::Matches($InsideLoopLine,'(?<=\().*(?=\))')

New info 1 : @WiktorStribiżew

Code:

$Line = 'to devices Headset Earphone (Some Device)'
([regex]::Matches($Line,'\bto devices Headset.*?\(([^()]+)')).Value

Result:

to devices Headset Earphone (Some Device

New info 2

Code:

$Line = 'to devices Headset Earphone (Some Device)'
([regex]::Matches($Line,'\bto devices Headset.*?\(([^()]+)')).Groups[1].Value

Result:

Some Device
powershell regex .net c#
2 Answers
$Query = [regex]::Matches($Line, "to devices Headset Earphone \((.*)\)")
$Query.Groups[1].Value
user_91640150

You may use -match with a pattern containing a capturing group, then, once there is a match, you may access your expected value using $matches[1]:

PS C:\Users\admin> $line = 'to devices Headset Earphone (Some Device)'
PS C:\Users\admin> $s -match '\bto devices Headset.*?\(([^()]+)' | Out-Null
PS C:\Users\admin> $matches[1]
Some Device

See the regex demo at a .NET regex compatible testing site.

Details

  • \bto devices Headset - whole word to, then space and devices Headset text
  • .*? - any 0 or more chars other than a newline, as few as possible
  • \( - a ( char
  • ([^()]+) - Capturing group 1: any one or more chars other than ( and ).

You may check if there was a match before:

PS C:\Users\admin> $matched = $s -match '\bto devices Headset.*?\(([^()]+)'
PS C:\Users\admin> if ($matched) { Write-Host $matches[1] }

Alternative with [regex]::Match:

PS C:\Users\admin> $result = [regex]::Match($line, '(?<=\bto devices Headset.*?\()[^()]+').value
PS C:\Users\admin> $result
Some Device
user_38329700
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