#include <StringConstants.au3> ; to declare the Constants of StringRegExp
#include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate
Local $sRegex = "(?m)\/a\/b\/c\/([^\W_]+)(?:_([0-9]+))?\/p1=(.*)\/p2=(.*)\/p3=(.*)\/(.*)"
Local $sString = "/a/b/c/d_9000/p1=<val1>/p2=<val2>/p3=<val3>/<val4>" & @CRLF & _
"/a/b/c/d/p1=<val1>/p2=<val2>/p3=<val3>/<val4>"
Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH)
Local $aFullArray[0]
For $i = 0 To UBound($aArray) -1
_ArrayConcatenate($aFullArray, $aArray[$i])
Next
$aArray = $aFullArray
; Present the entire match result
_ArrayDisplay($aArray, "Result")
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm