#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?m)<a href=".*?""
Local $sString = "<td>" & @CRLF & _
"[<a href="/abc123/handouts/files/directory1/somename.pdf" target="_blank">Slides</a> ] [ [<a href="/abc123/handouts/files/directory2/somename2.pdf" target="_blank">Handout</a> ]</td>" & @CRLF & _
"" & @CRLF & _
"<td>" & @CRLF & _
"[<a href="/abc123/handouts/files/directory3/somename343.pdf" target="_blank">Slides</a> ] [ <a href="/abc123/handouts/files/directory5/somename2324.pdf" target="_blank">Handout</a> ]" & @CRLF & _
"</td>"
Local $sSubst = "<a href="#""
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