#include <StringConstants.au3> ; to declare the Constants of StringRegExp
#include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate
Local $sRegex = "(?si)<item>.*?<id>((?:(?!<id>).)*?)</id>(?:(?!<item>).)*<img>(.*?)</img>.*?</item>"
Local $sString = "<set>" & @CRLF & _
"<item>" & @CRLF & _
" <id>1</id>" & @CRLF & _
" <title>title1</title>" & @CRLF & _
"</item>" & @CRLF & _
"<item>" & @CRLF & _
" <id>2</id>" & @CRLF & _
" <title>title2</title>" & @CRLF & _
"</item>" & @CRLF & _
"<item>" & @CRLF & _
" <id>3</id>" & @CRLF & _
" <title>title3</title>" & @CRLF & _
" <img>img3</img>" & @CRLF & _
"</item> " & @CRLF & _
"</set>"
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