#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?m)\[(block-([0-9]+))\](.+?)\[\/\1\]"
Local $sString = "[block-2] "Donec volutpat nibh sit amet libero ornare non laoreet arcu luctus. Donec id arcu quis mauris". [/block-2]"
Local $sSubst = "<blockquote class="tm-style\2"><span>\n\3\n</span></blockquote>"
Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst)
MsgBox($MB_SYSTEMMODAL, "Result", $sResult)
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