#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?:\b|\d+)([a-z])|[\d+ +!.@]"
Local $sString = "Th3 qu!ck br0wn f0x jumps 0v3r th3 l@zy d0g. "
Local $sSubst = "\U\1"
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