Question

我想从网址下载图片，例如：http://trinity.e-stile.ru/并将图片保存到＆＃34; C：\ pickaxe \ pictures＆＃34;等目录中。使用Nokogiri非常重要。

我在本网站上阅读了类似的问题，但我没有找到它是如何工作的，我也不了解算法。

我编写了代码，用于解析网址并将部分网页源代码放入＆＃34; img＆＃34;标记到链接对象：

require 'nokogiri'
require 'open-uri'

PAGE_URL="http://trinity.e-stile.ru/"
page=Nokogiri::HTML(open(PAGE_URL))   #parsing into object
links=page.css("img") #object with html code with img tag
puts links.length # it is 24 images on this url
puts
links.each{|i| puts i } #it looks like: <img border="0" alt="" src="/images/kroliku.jpg"> 
puts
puts
links.each{|link| puts link['src'] } #/images/kroliku.jpg

抓取HTML代码后用什么方法保存图片？

我更改了代码，但它有一个错误：

/home/action/.parts/packages/ruby2.1/2.1.1/lib/ruby/2.1.0/net/http.rb:879:in `initialize': getaddrinfo: Name or service not known (SocketError)

这是现在的代码：

require 'nokogiri'
require 'open-uri'
require 'net/http'

LOCATION = 'pics'
if !File.exist? LOCATION         # create folder if it is not exist
    require 'fileutils'
    FileUtils.mkpath LOCATION
end

#PAGE_URL = "http://ruby.bastardsbook.com/files/hello-webpage.html"
#PAGE_URL="http://trinity.e-stile.ru/"
PAGE_URL="http://www.youtube.com/"
page=Nokogiri::HTML(open(PAGE_URL))   
links=page.css("img")

links.each{|link| 
    Net::HTTP.start(PAGE_URL) do |http|
      localname = link.gsub /.*\//, '' # left the filename only
      resp = http.get link['src']
      open("#{LOCATION}/#{localname}", "wb") do |file|
        file.write resp.body
      end
    end
 }

Answer 1

你差不多完成了。唯一剩下的就是存储文件。我们来做吧。

LOCATION = 'C:\pickaxe\pictures'
if !File.exist? LOCATION         # create folder if it is not exist
    require 'fileutils'
    FileUtils.mkpath LOCATION
end

require 'net/http'
.... # your code with nokogiri etc.
links.each{|link| 
    Net::HTTP.start(PAGE_URL) do |http|
      localname = link.gsub /.*\//, '' # left the filename only
      resp = http.get link['src']
      open("#{LOCATION}/#{localname}", "wb") do |file|
        file.write resp.body
      end
    end
end

就是这样。

Answer 2

正确的版本：

require 'nokogiri'
require 'open-uri'


LOCATION = 'pics'
if !File.exist? LOCATION         # create folder if it is not exist
    require 'fileutils'
    FileUtils.mkpath LOCATION
end

#PAGE_URL="http://trinity.e-stile.ru/"
PAGE_URL="http://www.youtube.com/"

page=Nokogiri::HTML(open(PAGE_URL)) 
links=page.css("img")

links.each{|link|
  uri = URI.join(PAGE_URL, link['src'] ).to_s # make absolute uri
  localname=File.basename(link['src'])
   File.open("#{LOCATION}/#{localname}",'wb') { |f| f.write(open(uri).read) }
  }

如何将图片从URL保存到磁盘

2 个答案: