Quick Tip - PowerShell Regex To Get Value Between Quotation Marks
If you’ve got a value like the following…
$s = @" Here is: "Some data" Here's "some other data" this is "important" data "@
… that maybe came from the body of a file, was returned by some other part of a script, etc., and you just want the portions that are actually between the quotes, the quickest and easiest way to get it is through a regular expression match.
That’s right, forget splitting or trimming or doing other weird string manipulation stuff. Just use the [regex]::matches() feature of PowerShell to get your values.
Matches takes two parameters. 1. The value to look for matches in, in this case the here-string in my $s variable, and 2. The regular expression to be used for matching. Since Matches returns a few items, we are making sure to just select the value for each match.
So what is that regex doing? Let’s break it down into it’s parts.
- (?<=\") this part is a look behind as specified by the ?<= part. In this case, whatever we are matching will come right after a quote. Doing the look behind prevents the quotation mark itself from actually being part of the matched value. Notice I have to escape the quotation mark character.
- .+? this part basically matches as many characters as it takes to get to whatever the next part of the regex is. Look into regex lazy mode vs greedy mode.
- (?=\") this part is a look ahead as specified by the ?= part. We're looking ahead for a quotation mark because whatever comes after our match is done will be a quotation mark.
So basically what we’ve got is “whatever comes after a quotation mark, and as much of that as you need until you get to another quotation mark”. Easy, right? Don’t you love regex?