I need to get numbers out of a website script after a certain string - powershell-2.0

Question

I'm trying to get a certain string of numbers (the numbers vary in length on each reload) out of a script tag on a website. However, I am struggling to figure out how to do it as I am stuck with PowerShell v2 and cannot upgrade it higher.
I've managed to get the full script by getting element by loading the site in IE and getting element by tag name "script" and I've attempted to try some regex to find the string but can't quite figure it out.
I have also tried stripping the characters off the front and back of the script, that's when I realised the lengths of the numbers change each time.
Part of the script is:
var value = document.wizform.selActivities.options[document.wizform.selActivities.selectedIndex].value;
if (value == "Terminate") {
if (confirm("Are you sure you want to terminate the selected business process(es)?")) {
document.wizform.action = "./Page?next=page.actionrpt&action=terminate&pos=0&1006999619";
javascript:document.wizform.submit();
}
} else if (value == "TerminateAndRestart") {
if (confirm("Are you sure you want to terminate and restart the selected business process(es)?")) {
document.wizform.action = "./Page?next=page.actionrpt&action=terminateandrestart&pos=0&237893352";
javascript:document.wizform.submit();
}
}
The part I want to capture is the numbers here
document.wizform.action = "./Page?next=page.actionrpt&action=terminateandrestart&pos=0&237893352";
The PowerShell code I have so far is
$checkbox = $ie.Document.getElementsByTagName("script") | Where-Object {
$_.outerHTML -like "*./Page?next=page.actionrpt&action=terminate*"
} # | select -Expand outerHTML
$content = $checkbox
$matches = [regex]::Matches($content, '".\action=terminate\.([^"]+)')
$matches | ForEach-Object {
$_.Groups[1].Value
}
What I would like is PowerShell to have just the number as a variable, so in the example above I would like to be able to have either 0&237893352 or just 237893352 (as the note does not change, so I can add the 0& back in after if I need to).

Answer 1

Use a positive lookbehind assertion for matching the particular action you're interested in:
$re = '(?<=action=terminateandrestart&pos=)0&\d+'
$content |
Select-String -Pattern $re |
Select-Object -Expand Matches |
Select-Object -Expand Value
(?<=...) is a regular expression construct called "positive lookbehind assertion" that allows for matching something that is preceded by a particular string (in your case "action=terminateandrestart&pos=") without making that string part of the returned match. This way you can look for the string "action=terminateandrestart&pos=" followed by "0&" and one or more digits (\d+) and return only "0&" and the digits.