require 'uri'

uri = URI("http://foo.com/posts?id=30&limit=5#time=1305298413")

#=> #<URI::HTTP:0x00000000b14880

      URL:http://foo.com/posts?id=30&limit=5#time=1305298413>

uri.scheme

#=> "http"

uri.host

#=> "foo.com"

uri.path

#=> "/posts"

uri.query

#=> "id=30&limit=5"

uri.fragment

#=> "time=1305298413"

uri.to_s

#=> "http://foo.com/posts?id=30&limit=5#time=1305298413"

URI.encode_www_form([["q", "ruby"], ["lang", "en"]])

#=> "q=ruby&lang=en"

URI.encode_www_form("q" => "ruby", "lang" => "en")

#=> "q=ruby&lang=en"

URI.encode_www_form("q" => ["ruby", "perl"], "lang" => "en")

#=> "q=ruby&q=perl&lang=en"

URI.encode_www_form([["q", "ruby"], ["q", "perl"], ["lang", "en"]])

#=> "q=ruby&q=perl&lang=en"

ary = URI.decode_www_form("a=1&a=2&b=3")

p ary                  #=> [['a', '1'], ['a', '2'], ['b', '3']]

p ary.assoc('a').last  #=> '1'

p ary.assoc('b').last  #=> '3'

p ary.rassoc('a').last #=> '2'

p Hash[ary]            # => {"a"=>"2", "b"=>"3"}

require 'uri'

p URI.encode('http://www.ruby-lang.org/ja/man-1.6/?cmd=view;name=Ruby参考手册')
#=> http://www.ruby-lang.org/ja/man-1.6/?cmd=view;name=Ruby%B2%CE%BF%BC%CA%D6%B2%E1

require 'uri'

p URI.unescape('http://www.ruby-lang.org/ja/man-1.6/?cmd=view;name=Ruby%B2%CE%BF%BC%CA%D6%B2%E1')

#=> http://www.ruby-lang.org/ja/man-1.6/?cmd=view;name=Ruby参考手册