从nodejs xml2js'结果'中提取信息

Question

使用 xml2js nodejs 模块，我已经成功地使用以下代码从（大！）xml 文档中提取；

var fs = require('fs'),
    parseString = require('xml2js').parseString,
    request = require('request');
    request('https://fb.motorcyclenews.com/mcn-bfs-fb-marketplace.xml', function (error, response, body) {
       if (!error && response.statusCode == 200) {
          parseString(body, function (err, result) {
            console.log(JSON.stringify(result));
          });
     }});

这个“有效”，结果的一小部分摘录如下；

"dealer_id":["--"],"dealer_name":["-- 摩托车"],"vehicle_registration_plate":["--"],"fb_page_id":["--"],"dealer_communication_channel":["LEAD_FORM"],"dealer_phone":["+44 --"],"dealer_privacy_policy_url":["https://www.motorcyclenews.com/privacy-policy/"],"mileage":[{"value":["552"],"unit":[" MI"]}],"address":[{"$":{"format":"simple"},"component":[{"":"Ivy 路车库","$":{"name":"addr1"}},{"":"Ivy 路","$":{"name":"city"}},{"":"Lancashire","$":{"name":"region"}},{" ":"UK","$":{"name":"country"}},{"":"-- 6DJ","$":{"name":"postal_code"}}]}],"vehicle_type":["MOTORCYCLE"],"dealer_url":["https://www.motorcyclenews.com/api/bfs -dealer/redirect/--"]},{"vehicle_id":["56968134"],"make":["HONDA"],"model":["NSS300 FORZA"],"year":["2018"],"transmission":["OTHER"],"body_style":["OTHER"],"fuel_type":["GASOLINE"],"drivetrain":[" RWD"],"描述":["本田 FORZA 300CC ULTRA LOW MILES，配备顶盒，护手，加热把手， 完好无损，为什么要坐火车或公共汽车节省时间和金钱，价格低 成本融资全国交付 可用。"],"图片":[{"url":["https://cdn.images.autoexposure.co.uk/AETA86362/AETV24605587_5.jpg?t=--"]}],"url": [“https://www.motorcyclenews.com/bikes-for-sale/honda/nss300-forza/--/”]，“标题”：[“本田 NSS300 FORZA (2018)"],"价格":["3,750.00 GBP"],"state_of_vehicle":["USED"],"exterior_color":["BLACK"],"latitude":["51.7241967327"],"longitude":["0.4833483158"],"dealer_id":[" -- City Motorcycles LTD"],"dealer_name":["-- City Motorcycles LTD"],"vehicle_registration_plate":["--"],"fb_page_id":["--"],"dealer_communication_channel":["LEAD_FORM"],"dealer_phone":["+44 --"],"dealer_privacy_policy_url":["https://www.motorcyclenews.com/privacy-policy/"],"mileage":[{"value":["1793"],"unit":[" MI"]}],"地址":[{"$":{"format":"simple"},"component":[{"":"198-200 巴多 路","$":{"name":"addr1"}},{"":"未知","$":{"name":"city"}},{" ":"埃塞克斯","$":{"name":"region"}},{"":"UK","$":{"name":"country"}},{"":"CM2 9QP","$":{"name":"postal_code"}}]}],"vehicle_type":["MOTORCYCLE"],"dealer_url":["https://www.motorcyclenews.com/api/bfs -dealer/redirect/--"]},{"vehicle_id":["56970343"],"make":["HONDA"],"model":["VISION 110"],"year":["2011"],"transmission":["OTHER"],"body_style":["OTHER"],"fuel_type":["GASOLINE"],"drivetrain":[" RWD"],"description":[""],"url":["https://www.motorcyclenews.com/bikes-for-sale/honda/vision-110/--

/"],"title":["本田

VISION 110 (2011)"],"price":["1,250.00 GBP"],"state_of_vehicle":["USED"],"exterior_color":["Red"],"latitude":["52.2398688251"],"longitude":["0.752311123"],"dealer_id":["约翰 班克斯本田摩托车"],"dealer_name":["约翰 -- 本田 摩托车"],"vehicle_registration_plate":["--"],"fb_page_id":["7714743854"],"dealer_communication_channel":["LEAD_FORM"],"dealer_phone":["+44 --"],"dealer_privacy_policy_url":["https://www.motorcyclenews.com/privacy-policy/"],"mileage":[{"value":["5051"],"unit":[" MI"]}],"address":[{"$":{"format":"simple"},"component":[{"":"Kempson 方式","$":{"name":"addr1"}},{"":"Moreton 方式","$":{"name":"city"}},{"":"Suffolk","$":{"name":"region"}},{" ":"UK","$":{"name":"country"}},{"":"-- 7AR","$":{"name":"postal_code"}}]}],"vehicle_type":["MOTORCYCLE"],"dealer_url":["https://www.motorcyclenews.com/api/bfs -dealer/redirect/--"]},{"vehicle_id":["--"],"make":["HONDA"],"model":["CRF250"],"year":["2019 "],"transmission":["OTHER"],"body_style":["OTHER"],"fuel_type":["GASOLINE"],"drivetrain":["RWD"],"description":["" ],"url":["https://www.motorcyclenews.com/bikes-for-sale/honda/crf250/--/"],"title":["HONDA CRF250 (2019)"],"价格":["4,500.00 GBP"],"state_of_vehicle":["USED"],"exterior_color":["Red"],"latitude":["52.2398688251"],"longitude":["0.752311123"],"dealer_id":["约翰 班克斯本田摩托车"],"dealer_name":["约翰 -- 本田 摩托车"],"vehicle_registration_plate":["--"],"fb_page_id":["7714743854"],"dealer_communication_channel":["LEAD_FORM"],"dealer_phone":["+44 --"],"dealer_privacy_policy_url":["https://www.motorcyclenews.com/privacy-policy/"],"mileage":[{"value":["1000"],"unit":[" MI"]}],"address":[{"$":{"format":"simple"},"component":[{"":"Kempson 方式","$":{"name":"addr1"}},{"":"Moreton 方式","$":{"name":"city"}},{"":"Suffolk","$":{"name":"region"}},{" ":"UK","$":{"name":"country"}},{"":"-- 7AR","$":{"name":"postal_code"}}]}],"vehicle_type":["MOTORCYCLE"],"dealer_url":["https://www.motorcyclenews.com/api/bfs -dealer/redirect/--"]}]}}

但我现在想做的是从中提取一些信息。

我特别想知道列表中出现了多少次，例如“vehicle_id”的条目。

然后我可以将它用于我的测试的其他部分。

任何帮助将不胜感激。

谢谢

Answer 1

假设你发布的输出是一个对象，试试这个

let finalResult = Object.keys(result).reduce( (allNames, name) => { 
  if (name in allNames && name === "vehicle_id") {
    allNames[name]++
  }
  else if(name === "vehicle_id") {
    allNames[name] = 1
  }
  return allNames
}, {})

console.log(finalResult)