Regex Mystery - 你能帮我添加这些选项吗？

Question

The problem

My regex below for a PHP preg_replace works great

 '|(?<!</h2>)\s*
(?!<h2>)|'

However I would much rather the 'h2' part be a section which searches for any of 'h2|p|li|div' etc, just whatever it can find out of the choices I give it.

I have tried all sorts like

'|(?<!</(?:h2|p|li|div)>)\s*
(?!<(?:h2|p|li|div)>)|'

But it just will not seem to work.

This would be a great help if anyone can point me in the correct direction as I am working this out as an alternative to a problem I posted yesterday.

Extra notes

My aim for the code BTW is to FIND ALL LINE BREAKS ( ) that DO NOT have a /h2 or /p etc BEFORE the line break and DO NOT have a h2 or p etc AFTER the linebreak. So....

example
                        <- find this
example
                        <- find this
example
                        <- not this (as <h2> next starts line)
<h2>example
                    <- find this
example</h2>
                   <- not this (as </h2> ends this line)
example
                        <- find this

Many many thanks,

Answer 1

I would just use this:

~<(h2|p|li|div)([^\>]+)?>([^\<]+)?</(h2|p|li|div)>~

That accounts for stuff like class="xyz" in the opening tag.

This will fix the regex you provided, but if you want to accomplish what you described at the bottom of your question, you'll probably need something more complicated.