preg_replace仅删除结束标记

Question

I'm working on a joomla site that use JotCache as cache component. To exclude from cache some modules directly on template files, this component use own "markers" such as:

<jot myposition s> Module Position <jot myposition e>

Now, i'm trying to minify html trough php using DOMDocument but the result is this and the cache component doesn't work:

<jot myposition s> Module Position <jot myposition e></jot></jot>

I'm thinking to use preg_replace to strip the </jot> closing tag. I tried this regex "/<[\/]*jot[^>]*>/i" but it strips all <jot> tags, including the required <jot myposition s> and <jot myposition e>.

Since I'm not sure how to accomplish this with DOMDocument (prevent tags closing automatically), how can I do this with preg_replace?

Any ideas would be very appreciated.

Thanks.

Answer 1

A Nice Chance to Explore some Regex Features!

With all the disclaimers about using regex to work with xml-type documents... There are several interesting options for such a task.

Option 1: Plain but Reliable

$replaced = preg_replace('%(<jot.*?</jot>)</jot>%', '$1', $yourstring);

• Here, for safety, we match your whole string including the two </jot> at the end.
• The .*? "lazy dot-star" quantifier ensures we don't accidentally run past the first closing </jot>
• The parentheses capture the string you want to Group 1
• We replace with Group 1

Option 2: More "Cheeky"

$replaced = preg_replace('%</jot></jot>%', '</jot>', $yourstring);

• Here, we just match </jot></jot>
• We replace with </jot>

Option 3: Futuristic

$replaced = preg_replace('%</jot>(?=</jot>)%', '', $yourstring);

• Here, we match </jot>, then the lookahead (?=</jot>) asserts that </jot> can be found again, but doesn't match it.
• We replace with an empty string

Option 4: Keep Out!

$replaced = preg_replace('%<jot.*?</jot>\K</jot>%', '', $yourstring);

• As in the first option, <jot.*?</jot> matches a whole tag...
• Then \K tells the engine to drop whatever has been matched so far!
• and </jot> matches the second </jot>
• which we replace with the empty string