下载某页面下的所有图片

require 'net/http'
require 'fileutils'
require "open-uri"
response_html = Net::HTTP.get('url', '/', 3000)
response_html.scan(/<img.*?src=['"](.*?)['"].*?>/).each do |img|
  if img[0]==''
    next
  end
  img[0].scan(/[\/](.*)[\/](.*)/)
  FileUtils.mkdir_p($1)

  begin
    imguri = "url"+img[0].strip
    data=open(imguri){|f|f.read}
    open($1+'/'+$2,"wb"){|f|f.write(data)}
  rescue
    puts imguri
    #break
  end
end