删除空白子弹点（BBCode）

Question

Ok so I'm trying to come up with a PHP method that removes blank bullet point lists that I'm doing.

Here is an example I have:

http://rubular.com/r/01ydqcWx3Q

But I can't seem to get it to only grab the [*] that are blank so I can remove them... This is grabbing the non-blank ones.. so I could put it in the $matches variable below:

preg_match('/\[\*\][A-z0-9 ]+/', $body, $matches);

But.. I want the $matches to consist of the blank ones so I can just remove them.. or if there is a way to grab everything but the matches to remove except for the [list]..

As you can see, it's grabbing the [ in the [/list] which is not what I want either. Some of them will have only two blank, three blank, one blank, or ... more...

Any help would be appreciated.

Thank you!

Answer 1

If you’d like to match [*] with a regex, you have to escape all three characters with backslashes because they are meta-characters. Next, you have to find out if [*] is immediately followed by a newline ( or ) or end of list ([/list]). Then replace it with an empty string.

$body = "[list][*]Hydrogen
[*]
[*]Helium
[*]Lithium
[*]
[*]
[*]Beryllium
[*]Boron
[*]Carbon
[*]Nitrogen
[*]
[*]Oxygen
[*][/list]";
$body = preg_replace("/\[\*\](?:?
|(?=\[\/list\]))/", "", $body);
print($body);

The output will be:

[list][*]Hydrogen
[*]Helium
[*]Lithium
[*]Beryllium
[*]Boron
[*]Carbon
[*]Nitrogen
[*]Oxygen
[/list]