#include <StringConstants.au3> ; to declare the Constants of StringRegExp
#include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate
Local $sRegex = "(?mi)((?:https?:\/\/)?(?:www\.)?youtu\.?be(?:\.com)?\/(?!.*[?&]v=).*(?:list=)([\w-_]+)[^\s\'\"\.]*)"
Local $sString = "https://www.youtube.com/playlist?list=PLFgquLnL59akaNTxtgsoKn4c0Q8utjqku" & @CRLF & _
"http://www.youtube.com/embed/videoseries?list=PLdwCuEoZ_6l6C47ciTvf6Z2GArUOCHHQ3" & @CRLF & _
"https://www.youtube.com/watch?v=VTMcqVFk39s&index=2&list=PLxgKRG5rfVFa067PHSpju_XaTPiyii31L" & @CRLF & _
"https://www.youtube.com/watch?v=TpbTkbv4L2Y&list=PLvqxe4XbcSiEzrZm28NjsLXmHkffCJmBY&index=2 " & @CRLF & _
"https://www.youtube.com/watch?index=2&list=PLxgKRG5rfVFa067PHSpju_XaTPiyii31L&v=VTMcqVFk39s" & @CRLF & _
""
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