从方法

Question

我刚开始学习ruby，我正在尝试编辑以下脚本。代码是在创建目录时下载文件。

 def download_files
    puts "Downloading #{@base_url} to #{backup_path} from site..."
    puts
    file_list_by_time = get_file_list_by_time
    if file_list_by_time.count == 0
      puts "No files to download. Possible reasons:\n\t* Accept regex didn't let any files through (Accept Regex: \"#{@accept_regex.to_s}\")\n\t* Site is not in site."
      return
    end
    count = 0
    file_list_by_time.each do |file_remote_info|
      count += 1
      file_url = file_remote_info[:file_url]
      file_id = file_remote_info[:file_id]
      file_time = file_remote_info[:time]
      file_path_elements = file_id.split('/')
      if file_id == ""
        dir_path = backup_path
        file_path = backup_path + 'index.html'
      elsif file_url[-1] == '/' or not file_path_elements[-1].include? '.'
        dir_path = backup_path + file_path_elements[0..-1].join('/')
        file_path = backup_path + file_path_elements[0..-1].join('/') + '/index.html'
      else
        dir_path = backup_path + file_path_elements[0..-2].join('/')
        file_path = backup_path + file_path_elements[0..-1].join('/')
      end
      unless File.exists? file_path

                open('myfile.txt', 'a') do |f|
                f.puts ("http://example.com/#{file_time}id_/#{file_url}")
                end
        begin
          structure_dir_path dir_path
          open(file_path, "wb") do |file|
            begin

            rescue OpenURI::HTTPError => e
              puts "#{file_url} # #{e}"
             file.write(e.io.read)
            rescue StandardError => e
              puts "#{file_url} # #{e}"
            end
          end
        rescue StandardError => e
          puts "#{file_url} # #{e}"
        end
        puts "#{file_url} -> #{file_path} (#{count}/#{file_list_by_time.size})"
      else
        puts "#{file_url} # #{file_path} already exists. (#{count}/#{file_list_by_time.size})"
      end
    end
    puts
    puts "Download complete, saved in #{backup_path} (#{file_list_by_time.size} files)"
  end

end

我想将其更改为仅将完整文件URL保存为文本文件，即保存URL而不下载文件。

我将以下内容添加到完美运行的代码中。我现在只需要停止脚本下载文件。

  open('myfile.txt', 'a') do |f|
                f.puts ("http://example.com/#{file_time}id_/#{file_url}")
                end

我尝试将部分从structure_dir_path dir_path删除到最后，但我一直收到错误消息。任何想法如何才能正确实现？

Answer 1

从方法

早期返回

要停止处理，只需从方法内的任何位置返回，包括从块内返回。例如：

open('myfile.txt', 'a') do |f|
  url = "http://example.com/#{file_time}id_/#{file_url}"
  f.puts url
  return url
end

执行时禁用创建文件和目录

1 个答案:

从方法