Warning: preg_match() [function.preg-match]: Unknown modifier '/' [duplicate]

Answer 1

Try this:

preg_match('"http:\/\/(.+?)\"', $code, $matches);

Answer 2

preg_match('~"http://(.*)"~iU', $code, $matches);

Your issue was you need delimiters (I chose ~) to use with the pattern. See the preg_match() man page for more information.