Is there some open source php code available similar to the code used in vBulletin so that a user can add rich text (with html type commands) to a field in mysql?
I'm not sure if this is similar to vBulletin, but I have used 'HTMLArea' from InterActive Tools. The MySQL field should be set to 'LongText'. http://www.htmlarea.com/htmlarea_2/ Basically it's a simple WYSIWYG editor for 'textarea' fields on a form Hope this helps!
Use html code directly is something dangerous. Maybe that's why the popular open source use some special code (bbcode in phpBB, and dunno what vBulletin's code is)