Match text between two lines, suppose we have three lines of text
line1 theme_name:theme1 line3
We want to extract out the theme name, here the "theme1" string. We use windows line ending format.
preg_match('/line1\r\ntheme_name:([\s\S]*?)\r\nline3/', $text, $matches);
The matches will looks like
Array (  => line1 theme_name:theme1 line3  => theme1 )