specific regex help

[werd]

Been stumped on this for a while and would appreciate any guidance...

I need to parse some HTML using REGEX, here's the test html:

<TD id=AB44-itmz><A style="TEXT-ALIGN: center" id=AB45 class=urBtnStd tabIndex=0 href="javascript:void(0);" ct="B" ti="0"><IMG style="MARGIN-TOP: 0px" id=WD27-img border=0 align=absMiddle src="http://asdf.com/search_button.gif">&nbsp;<SPAN class=urBtnCntTxt>Search</SPAN></A></SPAN><SPAN id=WD28-rtbi class=urTbarItmBtn canHide="false"><A style="TEXT-ALIGN: center" id=DD17 class=urBtnStd tabIndex=0 href="javascript:void(0);" ct="B" ti="0" lsevents="{Press:[{ResponseData:'delta',ClientAction:'submit'},{}]}" lsdata="{0:'STANDARD',1:'',2:true,3:false,4:false,5:true,6:'',7:';aads/request_button.gif',8:'',9:false,10:'',11:false,12:'',13:'NONE',14:false,15:false,16:'',17:'NONE'}"><IMG style="MARGIN-TOP: 0px" id=WD28-img border=0 align=absMiddle src="http://asdf.com/request_button.gif">&nbsp;<SPAN class=urBtnCntTxt>Request</SPAN></A></SPAN><SPAN id=WD29-rtbi class=urTbarItmBtn canHide="false"><A style="TEXT-ALIGN: center" id=WD29 class=urBtnStd tabIndex=0 href="javascript:void(0);" ct="B" ti="0" lsevents="{Press:[{ResponseData:'delta',ClientAction:'submit'},{}]}" lsdata="{0:'STANDARD',1:'',2:true,3:false,4:false,5:false,6:'',7:'',8:'',9:false,10:'',11:false,12:'',13:'NONE',14:false,15:false,16:'',17:'NONE'}"><SPAN class=urBtnCntTxt>Merchant info.</SPAN></A></SPAN></TD></TR></TBODY></TABLE></DIV>

And I'm trying to grab the \id=.... \ value (having only 4 alphanumeric characters after the equal sign then a space) that first preceeds the text "Request". Here's the code I'm using:

\bid=([A-Z]{2}[0-9]{2,6})\s\b(?=class=urBtnStd .*Request)

Right now, I know this is incorrect because it's returning both "id=AB45" and "id=DD17". How can I grab just the "id=DD17" which will correspond to the "Request" text?

thanks in advance,

wd

[GEOSoft]

this should always get the last one before the request text.

"(?i)<td.+bid=([[:alpha:]]{2}[0-9]{2,6})sb(?=class=urBtnStd .*Request)"

[werd]

Thanks that works... but I'm frustrated that I don't understand why it works. can you shed any light on how the "<td.+" makes this work?

[JohnQSmith]

Here's how RegexBuddy explains it.

Match the remainder of the regex with the options: case insensitive (i) «(?i)»
Match the characters “<td” literally «<td»
Match any single character that is not a line break character «.+»
   Between one and unlimited times, as many times as possible, giving back as needed (greedy) «+»
Assert position at a word boundary «\b»
Match the characters “id=” literally «id=»
Match the regular expression below and capture its match into backreference number 1 «([[:alpha:]]{2}[0-9]{2,6})»
   Match a single character present in the list below «[[:alpha:]]{2}»
      Exactly 2 times «{2}»
      A character in the POSIX character class “alpha” «[:alpha:]»
   Match a single character in the range between “0” and “9” «[0-9]{2,6}»
      Between 2 and 6 times, as many times as possible, giving back as needed (greedy) «{2,6}»
Match a single character that is a “whitespace character” (spaces, tabs, and line breaks) «\s»
Assert position at a word boundary «\b»
Assert that the regex below can be matched, starting at this position (positive lookahead) «(?=class=urBtnStd .*Request)»
   Match the characters “class=urBtnStd ” literally «class=urBtnStd »
   Match any single character that is not a line break character «.*»
      Between zero and unlimited times, as many times as possible, giving back as needed (greedy) «*»
   Match the characters “Request” literally «Request»

[GEOSoft]

the '<td' wasn't really important. it's only there because of the possibility that the match could also be found elsewhere on the page and we didn't get to see the whole page.

the '.+' just told it to skip everything up to the last match.

the pcre toolkit in my signature will allow you to load a web page for testing the expressions to see the results before you commit the code to your script and when you have it working the way you want you can just export it directly to scite by clicking the blue button at the upper right if you have scite set as the export mode in options.

[werd]

Thanks much -- i get it now.