What exactly do you want to do?

Or perhaps you simply forgot to include your payment.

And you surely forgot to read the directions for posting code and data which are boldfaced just below the text input box.

Therefore, as a path to enlightenment, read On asking for help, How do I post a question effectively? and Markup in the Monastery.

And just by the way, regexen are generally not the wisest way to deal with XML. See the xml modules at http://www.cpan.org/.

Also see ?node_id=3989;HIT=xml%20reg;re=N

2011-04-21	sachin_gurumukhi	Need to write a regular expression in perl for the below xml code.	SoPW
2011-02-16	satishchandra	How to find XML tags using regular expression	SoPW
2010-12-13	Zapano	regex and XML	SoPW
2010-09-30	ethrbunny	XML / regex - cleaning up attributes	SoPW
2010-09-21	ethrbunny	XML cleanup - regex or ?	SoPW
2010-07-07	ad23	Parse XML with Perl regex	SoPW
2010-06-18	equick	perl regex for xml	SoPW
2010-02-16	pavanmach	Regarding XML::DOM	SoPW
2009-11-20	kcvenkat123	REGEX negate XML tags	SoPW
2009-10-06	dalegribble	Regular expression to replace xml data	SoPW
2009-09-16	mecrazycoder	Regarding XML::DOM::Parser	SoPW
2009-06-27	Anonymous Monk	Regular expression to check XML type	SoPW
2008-06-16	Anonymous Monk	Regular Expression XML Searching Help	SoPW
2008-02-22	slloyd	Regular expression - parsing and xml string	SoPW
2008-02-16	karpatov	XML parsing vs Regular expressions	SoPW
2007-10-24	gasho	Removing XML comments with regex	SoPW
2005-11-18	starbuck	Regexp magic needed, truncate incomplete XML	SoPW
2004-08-29	amonroy	XML::Twig disregarding map_xmlns in the constructor	SoPW
2004-02-25	butlerdi	Regex et XML	SoPW
2004-02-17	bear0053	regex on XML	SoPW
2003-11-20	inblosam	Regex and a pseudo-XML tag	SoPW
2002-05-14	ctgIT	XML-related Regular Expression question	SoPW
2001-08-23	tshabet	Regex for XML attributes...	SoPW
2001-06-11	John M. Dlugosz	XML-related Regular Expressions	Snippet
2001-06-10	epoptai	Regex to encode entities in XML	SoPW
2000-11-26	Leitchn	Using regexps to parse an XML DTD file	SoPW

My response is directed toward your subject line for this post, as the content of the post doesn't ask a question, or even put forth a need.

You said you need to write a regular expression in Perl for XML code. All I can contribute to such a vague statement of design specification is that, having used XML to some extent, I haven't ever had to write a regular expression to parse XML. That's not to say regular expressions aren't used in the course of XML parsing with Perl, but they're generally encapsulated in modules that do the heavy lifting for you. The advantage to such modules is that they're well thought out, refined, heavily tested, and have passed through the hot forge of large user-bases.

You can write your own XML parser if you wish. But when General Motors builds a car, they don't boil the rubber out of trees from the Amazon to make their tires. In fact, they don't even make tires; they buy them from a supplier who has more experience in that specific aspect of manufacturing. GM could, if they wanted to, manufacture their own tires. But they've realized that it's beneficial to let an expert handle that detail for them.

I recommend you have a look at a few of the following CPAN modules: XML::Twig, XML::Simple, XML::LibXML::Parser... there are many others well tested and highly thought of. But these cover a broad array of needs. Yes, even you can use CPAN. If you're on ActiveState Perl, look at PPM to see what it has to offer for XML modules. If you're on a kinder flavor of Perl (Strawberry, or most Linux environments), it's as easy as typing "cpan install module::name."