Get the word before & after '_-_' with REGEX PowerShell - regex

Question

I am trying to get the Word before and decimal string following a non guaranteed string that looks like ' - '.
Consider this string
"some str (targetWord - 12434 trailing string)"
this string is not guaranteed to have spaces before or after the '-'
so it could look like one of the following
"some str (targetWord-12434 trailing string)"
"some str (targetWord- 12434 trailing string)"
"some str (targetWord -12434 trailing string)"
"some str (targetWord- 12434 trailing string)"
So far I have the following
$allServices = (Get-Service "Known Service Prefix*").DisplayName
foreach ($service in $allServices){
$service = $service.split('\((.*?)\)')[1] #esc( 'Match any non greedy' esc)
if($service.split()[0] -Match '-'){
$arr_services += $service.split('( - )')[0..1]
}else{
$arr_services += ($service -replace '-','').split()[0..1]
}
}
This works to handle the simple case of ' - ' & '-', but cant handle anything else. I feel like this is the kind of problem that could be handled by one line of REGEX or at most two.
What I want to end up with is an array of strings, where the evens (including zero) are the targetWord, and the odd values are the decimal strings.
My issue isn't that I can't make this happen, it's that it looks like crap...
what I mean is my goal is to try and use REGEX to get each word, ignore the '-', and push out to a growing array the targetWord & decimalString.
I see this as more of a puzzle than anything and am trying to use this to improve my REGEX skills. Any help is appreciated!

Answer 1

A single regex passed to the -match operator should suffice:
$arr_services = $allServices | ForEach-Object {
if ($_ -match '\((?<word>\w+) *- *(?<number>\d+)') {
# Output the word and number consecutively.
$Matches.word, $Matches.number
}
}
# Output the resulting array.
$arr_services
Note how the pipeline output can be directly collected in a variable as an array ($arr_services = ...) - no need to iteratively "add" to an array. If you need to ensure that $arr_services is always an array - even if the pipeline outputs only one object, use [array] $arr_services = ...
With your sample strings, the above yields (a flat array of consecutive word-number pairs):
targetWord
12434
targetWord
12434
targetWord
12434
targetWord
12434
As for the regex:
\( matches a literal (
\w+ matches a nonempty run (+) of word characters (\w - letters, digits, _), captured in named capture group word ((?<word>...).
 *- * matches a literal - surrounded by any number of spaces - including none (*).
\d+ matches a nonempty run of digits (\d), captured in named group digits.
if the -match operator finds a match, the results are reflected in the automatic $Matches variable, a hashtable that enables accessing named capture groups directly by name.

Answer 2

here's one way to handle the data set you posted. it presumes all the strings will have the same general format that you posted. that means it WILL FAIL if your sample data set is not realistic. [grin]
$InStuff = #(
'some str (targetWord - 12434 trailing string)'
'some str (targetWord-12434 trailing string)'
'some str (targetWord- 12434 trailing string)'
'some str (targetWord -12434 trailing string)'
'some str (targetWord- 12434 trailing string)'
)
$Results = foreach ($IS_Item in $InStuff)
{
$Null = $IS_Item -match '.+\((?<Word>.+) *- *(?<Number>\d{1,}) .+\)'
[PSCustomObject]#{
Word = $Matches.Word.Trim()
Number = $Matches.Number
}
}
$Results
output ...
Word Number
---- ------
targetWord 12434
targetWord 12434
targetWord 12434
targetWord 12434
targetWord 12434