preg_replace help needed for BBCode

Question

I can't quite figure out the right pattern to use with PHP's preg_replace function. Here is an example of some BBCode on a phpBB forum.

[color=black][font=Times New Roman][color=black]Thanks. As discussed last night/this morning, we were able to Cable and provide some small relief. After enough waste water was evacuated, the camera diagnosis found at 30 foot from clean-out, heavy root penetration and possible damage/separation to the line. We don’t want to throw a cost to fix/repair without a second opinion from xxx. We will have solid cost of repair later today of first thin in the morning. [/color][/font][/color]

I'd like to remove the opening and closing font tags, any number of them, that might be embedded in the text, but keep the text in between. In this case, I would like to end up with:

[color=black][color=black]Thanks. As discussed last night/this morning, we were able to Cable and provide some small relief. After enough waste water was evacuated, the camera diagnosis found at 30 foot from clean-out, heavy root penetration and possible damage/separation to the line. We don’t want to throw a cost to fix/repair without a second opinion from xxx. We will have solid cost of repair later today of first thin in the morning. [/color][/color]

The name of the fonts vary, some have spaces in the names, some don't. The pattern match would have to work regardless.

Thanks in advance!

Answer 1

If you are simply removing them, you don't need a too complicated regex...

$str = '[color=black][font=Times New Roman][color=black]Thanks. As discussed last night/this morning, we were able to Cable and provide some small relief. After enough waste water was evacuated, the camera diagnosis found at 30 foot from clean-out, heavy root penetration and possible damage/separation to the line. We don’t want to throw a cost to fix/repair without a second opinion from xxx. We will have solid cost of repair later today of first thin in the morning. [/color][/font][/color]';

$regex = '/\[font=.*?\]|\[\/font\]/i';

$str = preg_replace($regex, '', $str);

var_dump($str);

Outputs

string(457) "[color=black][color=black]Thanks. As discussed last night/this morning, we were able to Cable and provide some small relief. After enough waste water was evacuated, the camera diagnosis found at 30 foot from clean-out, heavy root penetration and possible damage/separation to the line. We donÕt want to throw a cost to fix/repair without a second opinion from xxx. We will have solid cost of repair later today of first thin in the morning. [/color][/color]"

See it on ideone.