php - Make text between asterisks bold

Question

I wanted to make a PHP function that would make text bold between double asterisks, and italic between one asterisk, (quite like the editor on stackoverflow).

Same rules apply, if there's a space between the * and the word, it shouldn't render.

Who can help me out? I tried to, but I only came this far, as I don't know how to make the odd asterisks "< b >" and the even ones "< /b >".

(I can't type them without the spaces, stackoverflow will render the text between as bold.....)

$thenewtext = str_replace("**", "<b>", "**Hello World** of PHP");

Answer 1

A simple regex will do the trick:

$thenewtext = preg_replace('#*{2}(.*?)*{2}#', '<b>$1</b>', '**Hello World** of PHP');