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hello - Marco Demaio Apr 30 '11 at 17:31 | Show 3 more comments 182 Sun Tzu, an ancient Chinese strategist, general, and philosopher, said: It is said that if you know your enemies and know yourself, you can win a hundred battles without a single loss. If you only know yourself, but not your opponent, you may win or may lose. If you know neither yourself nor your enemy, you will always endanger yourself. In this case your enemy is HTML and you are either yourself or regex. You might even be Perl with irregular regex. Know HTML. Know yourself. I have composed a haiku describing the nature of HTML. HTML has complexity exceeding regular language. I have also composed a haiku describing the nature of regex in Perl. The regex you seek is defined within the phrase <([a-zA-Z]+)(?:[^>]*[^/]*)?> Share Improve this answer Follow edited Oct 5 '13 at 4:52 community wiki 2 revs, 2 users 98% cytinus 0 Add a comment | 155 foo

name

'; $dom = new DOMDocument(); $dom->loadHTML($html); $els = $dom->getElementsByTagName('*'); foreach ( $els as $el ) { $nodeName = strtolower($el->nodeName); if ( !in_array( $nodeName, $selfClosing ) ) { var_dump( $nodeName ); } } Output: string(4) "html" string(4) "body" string(1) "p" string(1) "a" string(3) "div" Basically just define the element node names that are self closing, load the whole html string into a DOM library, grab all elements, loop through and filter out ones which aren't self closing and operate on them. I'm sure you already know by now that you shouldn't use regex for this purpose. Share Improve this answer Follow edited Nov 15 '09 at 14:44 community wiki 2 revs meder 1 * 1 If you're dealing with real XHTML then append getElementsByTagName with NS and specify the namespace. - meder omuraliev Nov 15 '09 at 14:39 Add a comment | 149 I don't know your exact need for this, but if you are also using .NET, couldn't you use Html Agility Pack? Excerpt: It is a .NET code library that allows you to parse "out of the web" HTML files. The parser is very tolerant with "real world" malformed HTML. Share Improve this answer Follow answered Nov 16 '09 at 23:15 community wiki GONeale 1 * CodePlex closed down (but this one is in the CodePlex archive). Perhaps update? - Peter Mortensen Aug 14 '20 at 15:47 Add a comment | 138 You want the first > not preceded by a /. Look here for details on how to do that. It's referred to as negative lookbehind. However, a naive implementation of that will end up matching in this example document Can you provide a little more information on the problem you're trying to solve? Are you iterating through tags programatically? Share Improve this answer Follow edited Mar 19 '12 at 15:04 community wiki 2 revs, 2 users 89% Jherico 1 * 1 Yep, I sure am. Determining all the tags that are currently open, then compare that against the closed tags in a separate array. RegEx hurts my brain. - Jeff Nov 13 '09 at 23:04 Add a comment | 123 The W3C explains parsing in a pseudo regexp form: W3C Link Follow the var links for QName, S, and Attribute to get a clearer picture. Based on that you can create a pretty good regexp to handle things like stripping tags. Share Improve this answer Follow edited May 16 '14 at 14:43 community wiki 2 revs, 2 users 92% John-David Dalton 1 * 5 That's not a psuedo regexp form, that's an EBNF form, as specified here: XML spec, appendix 6 - Rob G Feb 11 '15 at 10:34 Add a comment | 107 If you need this for PHP: The PHP DOM functions won't work properly unless it is properly formatted XML. No matter how much better their use is for the rest of mankind. simplehtmldom is good, but I found it a bit buggy, and it is is quite memory heavy [Will crash on large pages.] I have never used querypath, so can't comment on its usefulness. Another one to try is my DOMParser which is very light on resources and I've been using happily for a while. Simple to learn & powerful. For Python and Java, similar links were posted. For the downvoters - I only wrote my class when the XML parsers proved unable to withstand real use. Religious downvoting just prevents useful answers from being posted - keep things within perspective of the question, please. Share Improve this answer Follow edited Mar 19 '12 at 15:02 community wiki 4 revs, 2 users 98% SamGoody 0 Add a comment | 96 Here's the solution: |>)/'; // a string to parse: $string = 'Hello, try clicking here
and check out.

title

Fine, thanks.

'; // let's get the occurrences: preg_match_all($pattern, $string, $matches, PREG_PATTERN_ORDER); // print the result: print_r($matches[0]); ?> To test it deeply, I entered in the string auto-closing tags like: 1.

2.
3.
I also entered tags with: 1. one attribute 2. more than one attribute 3. attributes which value is bound either into single quotes or into double quotes 4. attributes containing single quotes when the delimiter is a double quote and vice versa 5. "unpretty" attributes with a space before the "=" symbol, after it and both before and after it. Should you find something which does not work in the proof of concept above, I am available in analyzing the code to improve my skills. I forgot that the question from the user was to avoid the parsing of self-closing tags. In this case the pattern is simpler, turning into this: $pattern = '/<(\w+)(\s+(\w+)\s*\=\s*(\'|")(.*?)\\4\s*)*\s*>/'; The user @ridgerunner noticed that the pattern does not allow unquoted attributes or attributes with no value. In this case a fine tuning brings us the following pattern: $pattern = '/<(\w+)(\s+(\w+)(\s*\=\s*(\'|"|)(.*?)\\5\s*)?)*\s*>/'; Understanding the pattern If someone is interested in learning more about the pattern, I provide some line: 1. the first sub-expression (\w+) matches the tag name 2. the second sub-expression contains the pattern of an attribute. It is composed by: 1. one or more whitespaces \s+ 2. the name of the attribute (\w+) 3. zero or more whitespaces \s* (it is possible or not, leaving blanks here) 4. the "=" symbol 5. again, zero or more whitespaces 6. the delimiter of the attribute value, a single or double quote ('|"). In the pattern, the single quote is escaped because it coincides with the PHP string delimiter. This sub-expression is captured with the parentheses so it can be referenced again to parse the closure of the attribute, that's why it is very important. 7. the value of the attribute, matched by almost anything: (.*?); in this specific syntax, using the greedy match (the question mark after the asterisk) the RegExp engine enables a "look-ahead"-like operator, which matches anything but what follows this sub-expression 8. here comes the fun: the \4 part is a backreference operator, which refers to a sub-expression defined before in the pattern, in this case, I am referring to the fourth sub-expression, which is the first attribute delimiter found 9. zero or more whitespaces \s* 10. the attribute sub-expression ends here, with the specification of zero or more possible occurrences, given by the asterisk. 3. Then, since a tag may end with a whitespace before the ">" symbol, zero or more whitespaces are matched with the \s* subpattern. 4. The tag to match may end with a simple ">" symbol, or a possible XHTML closure, which makes use of the slash before it: (/>|>). The slash is, of course, escaped since it coincides with the regular expression delimiter. Small tip: to better analyze this code it is necessary looking at the source code generated since I did not provide any HTML special characters escaping. Share Improve this answer Follow edited Oct 18 '17 at 7:33 community wiki 6 revs, 2 users 96% Emanuele Del Grande 6 * 12 Does not match valid tags having attributes with no value, i.e.