我试图从这个网站中撷取表格中的各种元素来教导我自己使用node.js,cheerio和请求进行抓取
我无法获得表中的项目,本质上我想获得'rank','company'和'3-从表中可以看出年增长率。我该怎么做?
基于在线 tutorial ,我开发了我的scraping.js脚本,如下所示:
var request = require('request'), cheerio = require('cheerio'); request('www.inc/inc5000/index.html',function(error,response,html){ if(!error&& response.statusCode == 200){ var $ = cheerio.load(html); $('tr.ng-scope')。each(function(i,element){//问题可能在这里$ b $ (b)var a = $(this).get(0); console.log(a); }); } });然而,我确定我没有在右上方留言。有什么方法可以更好地访问表中的属性?
我注意到Xpaths是这样的
// * [@ id =col-r] / table / tbody / tr 2 / td 1 - rank
// * [@ id =col -r] / table / tbody / tr 2 / td 2 / a - 公司名称 $ b // * [@ id =col -r] / table / tbody / tr 2 a> / td [3] - 3年增长率
试图弄清楚如何访问这些属性据称..
解决方案您正确的方向。
$()。get()方法返回元素。在你的情况下, var a 是 TR 。这不一定就是你想要的。
你需要做的是将每一行进一步细分为单独的 TD '秒。我使用 $(this).find('td')来做到这一点。然后,我将每个 TD 1加1,然后从中提取文本,将其转换为一个对象,其中键代表表格的字段。所有这些都汇总到一个数组中,但是您可以使用基本概念来构建您认为适合使用的任何数据结构。
request('www.inc/inc5000/index.html',function(error,response,html){ if(error || response.statusCode!= 200)return; var $ = cheerio.load(html); var DATA = []; $ b $('tr.ng-scope')。each(function() { var $ tds = $(this).find('td'); DATA.push({等级:$ tds.eq(0).text( ),公司:$ tds.eq(1).text(),增长:$ tds.eq(2).text(),收入:$ tds.eq(3) ).text(), industry:$ tds.eq(4).text()}); }); console.log(DATA ); });
I am trying to scrape various elements in a table from this site to teach myself scraping using node.js, cheerio and request
I have trouble getting the items in the table, essentially I want to get 'rank','company' and '3-year growth' from the table. How do I do this?
Based on an online tutorial, I have developed my scraping.js script to look like this:
var request = require ('request'), cheerio = require ('cheerio'); request('www.inc/inc5000/index.html', function (error, response, html) { if (!error && response.statusCode == 200) { var $ = cheerio.load(html); $('tr.ng-scope').each(function(i, element){ //problem probably lies here var a = $(this).get(0); console.log(a); }); } });However, I am sure I am not getting the line with comment above right. Is there a way I can access the attributes in the table better?
I notice the Xpaths are as such
//*[@id="col-r"]/table/tbody/tr2/td1 -- rank
//*[@id="col-r"]/table/tbody/tr2/td2/a -- name of company
//*[@id="col-r"]/table/tbody/tr2/td[3] -- 3 year growth rate
Just trying to figure out how to access these attributes accordingly..
解决方案You're on the right track.
The $().get() method returns the element. In your case var a is the TR. That's not necessarily what you want.
What you need to do is further subdivide each row into the individual TD's. I did this using $(this).find('td'). Then, I grab each TD 1 by 1 and extract the text out of it, converting that into an object where the key represents the field of the table. All of these are aggregated into an array, but you can use the basic concept to build whatever data structure you see fit to utilize.
request('www.inc/inc5000/index.html', function (error, response, html) { if(error || response.statusCode != 200) return; var $ = cheerio.load(html); var DATA = []; $('tr.ng-scope').each(function(){ var $tds = $(this).find('td'); DATA.push({ rank: $tds.eq(0).text(), company: $tds.eq(1).text(), growth: $tds.eq(2).text(), revenue: $tds.eq(3).text(), industry: $tds.eq(4).text() }); }); console.log(DATA); });
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