regex - How do I return only the matching regular expression when I select-string(grep) in PowerShell?

Question

I am trying to find a pattern in files. When I get a match using Select-String I do not want the entire line, I just want the part that matched.

Is there a parameter I can use to do this?

For example:

If I did

select-string .-.-.

and the file contained a line with:

abc 1-2-3 abc

I'd like to get a result of just 1-2-3 instead of the entire line getting returned.

I would like to know the Powershell equivalent of a grep -o

Answer 1

Or just:

Select-String .-.-. .est.txt -All | Select Matches