^((http|https|ftp):\/\/)?([a-z]+\.)?[a-z0-9-]+(\.[a-z]{1,4}){1,2}(/.*\?.*)?$

匹配

http://www.example.com
www.example.com
example.com
example.info
abc.com.uk
www.example.co.in
www.example.com.sg
example.com.sg
t.com
co.co
https://www.t.co
asd.com.io/abc?foo=blah

误报

abc.com.sg.in
example.com.aero.uk