need a little help understanding the structure of this parser and parsers in general. I know how the function works and the array what i dont get is what: [i][b](.+?)[/b] [/i] [i][b]([0-9]{6})\](.+?)\ [/b][/i] [code]<?php function bbcode($string){ $string = nl2br(htmlspecialchars($string)); $patterns = array( '`\[b\](.+?)\[/b\]`is', '`\[i\](.+?)\[/i\]`is', '`\[u\](.+?)\[/u\]`is', '`\[strike\](.+?)\[/strike\]`is', '`\[color=#([0-9]{6})\](.+?)\[/color\]`is', '`\[email\](.+?)\[/email\]`is', '`\[img\](.+?)\[/img\]`is', '`\[url=([a-z0-9]+://)([\w\-]+\.([\w\-]+\.)*[\w]+(:[0-9]+)?(/[^ \"\n\r\t<]*?)?)\](.*?)\[/url\]`si', '`\[url\]([a-z0-9]+?://){1}([\w\-]+\.([\w\-]+\.)*[\w]+(:[0-9]+)?(/[^ \"\n\r\t<]*)?)\[/url\]`si', '`\[url\]((www|ftp)\.([\w\-]+\.)*[\w]+(:[0-9]+)?(/[^ \"\n\r\t<]*?)?)\[/url\]`si', '`\[flash=([0-9]+),([0-9]+)\](.+?)\[/flash\]`is', '`\[quote\](.+?)\[/quote\]`is', '`\[indent](.+?)\[/indent\]`is', '`\[size=([1-6]+)\](.+?)\[/size\]`is' ); $replaces = array( '<strong>\\1</strong>', '<em>\\1</em>', '<span style="border-bottom: 1px dotted">\\1</span>', '<strike>\\1</strike>', '<span style="color:#\1;">\2</span>', '<a href="mailto:\1">\1</a>', '<img src="\1" alt="" style="border:0px;" />', '<a href="\1\2">\6</a>', '<a href="\1\2">\1\2</a>', '<a href="http://\1">\1</a>', '<object width="\1" height="\2"><param name="movie" value="\3" /><embed src="\3" width="\1" height="\2"></embed></object>', '<strong>Quote:</strong><div style="margin:0px 10px;padding:5px;background-color:#F7F7F7;border:1px dotted #CCCCCC;width:80%;"><em>\1</em></div>', '<pre>\\1</pre>', '<h\1>\2</h\1>' ); $string = preg_replace($patterns, $replaces , $string); return $string; } ?> [/code]