Question

我有一个CSV，我喜欢在其上保存所有哈希值。我使用nokogiri sax来解析xml文档，然后将其保存为CSV。

sax解析器：

require 'rubygems'
require 'nokogiri'
require 'csv'

class MyDocument < Nokogiri::XML::SAX::Document

  HEADERS = [ :titles, :identifier, :typeOfLevel, :typeOfResponsibleBody, 
              :type, :exact, :degree, :academic, :code, :text ]

  def initialize
     @infodata = {}
     @infodata[:titles] = Array.new([])
  end

  def start_element(name, attrs)
    @attrs = attrs
    @content = ''
  end
  def end_element(name)
    if name == 'title'
      Hash[@attrs]["xml:lang"]
      @infodata[:titles] << @content
      @content = nil
    end
    if name == 'identifier'
       @infodata[:identifier] = @content
       @content = nil
    end
    if name == 'typeOfLevel'
       @infodata[:typeOfLevel] = @content
       @content = nil
    end
    if name == 'typeOfResponsibleBody'
       @infodata[:typeOfResponsibleBody] = @content
       @content = nil
    end
    if name == 'type'
       @infodata[:type] = @content
       @content = nil
    end
    if name == 'exact'     
       @infodata[:exact] = @content
       @content = nil
    end
    if name == 'degree'
       @infodata[:degree] = @content
       @content = nil
    end
    if name == 'academic'
       @infodata[:academic] = @content
       @content = nil
    end
    if name == 'code'
       Hash[@attrs]['source="vhs"']
       @infodata[:code] = @content 
       @content = nil
    end
    if name == 'ct:text'
       @infodata[:beskrivning] = @content
       @content = nil
    end 
  end
  def characters(string)
    @content << string if @content
  end
  def cdata_block(string)
    characters(string)
  end
  def end_document
    File.open("infodata.csv", "ab") do |f|
      csv = CSV.generate_line(HEADERS.map {|h| @infodata[h] })
      csv << "\n"
      f.write(csv)
    end
  end
end

为存储在文件夹中的每个文件（47.000xml文件）创建新对象：

parser = Nokogiri::XML::SAX::Parser.new(MyDocument.new)
counter = 0

Dir.glob('/Users/macbookpro/Desktop/sax/info_xml/*.xml') do |item|
  parser.parse(File.open(item, 'rb'))
  counter += 1
  puts "Writing file nr: #{counter}"
end

问题： 我没有为每一组新的值获得新的一行。有什么想法吗？

用于尝试代码的3个xml文件： https://gist.github.com/2378898 https://gist.github.com/2378901 https://gist.github.com/2378904

Answer 1

您需要使用“a”模式打开文件（打开带有“w”的文件会清除以前的任何内容）。

将数组附加到csv对象将自动插入换行符。 Hash＃values返回值的数组，但强制下订单会更安全。展平数组可能会导致列错位（例如[[：title1，：title2]，'other-value']将导致[：title1，：title2，'other-value']）。尝试这样的事情：

HEADERS = [:titles, :identifier, ...]

def end_document
  # with ruby 1.8.7
  File.open("infodata.csv", "ab") do |f|
    csv = CSV.generate_line(HEADERS.map { |h| @infodata[h] })
    csv << "\n"
    f.write(csv)
  end
  # with ruby 1.9.x
  CSV.open("infodata.csv", "ab") do |csv|
    csv << HEADERS.map { |h| @infodata[h] }
  end
end

执行以下操作可以验证上述更改：

require "csv"

class CsvAppender

  HEADERS = [ :titles, :identifier, :typeOfLevel, :typeOfResponsibleBody, :type,
              :exact, :degree, :academic, :code, :text ]

  def initialize
    @infodata = { :titles => ["t1", "t2"], :identifier => 0 }
  end

  def end_document
    @infodata[:identifier] += 1

    # with ruby 1.8.7
    File.open("infodata.csv", "ab") do |f|
      csv = CSV.generate_line(HEADERS.map { |h| @infodata[h] })
      csv << "\n"
      f.write(csv)
    end
    # with ruby 1.9.x
    #CSV.open("infodata.csv", "ab") do |csv|
    #  csv << HEADERS.map { |h| @infodata[h] }
    #end
  end

end

appender = CsvAppender.new

3.times do
  appender.end_document
end

File.read("infodata.csv").split("\n").each do |line|
  puts line
end

运行上述后，infodata.csv文件将包含：

"[""t1"", ""t2""]",1,,,,,,,,
"[""t1"", ""t2""]",2,,,,,,,,
"[""t1"", ""t2""]",3,,,,,,,,

Answer 2

我想你需要一个额外的循环。类似于

的东西

CSV.open("infodata.csv", "wb") do |csv|    
  csv << @infodata.keys
  @infodata.each do |key, value|
    csv << value
  end
end

将哈希值转换为CSV

2 个答案: