TypeError：无法读取图像URL的未定义属性'replace'

Question

因此，我尝试通过在udemy.com上观看有关node和cheerio的两个视频课程来独自学习如何做到这一点，但是我对此并没有任何改善。执行此操作时，代码将生成图像URL数组：

const request = require("request-promise");
const cheerio = require("cheerio");

const url = "https://www.example.com";

const scrapeResults = [];
async function scrapeJobHeader() {
  try {
    const htmlResult = await request.get(url);
    const $ = await cheerio.load(htmlResult);
    $("td.productListing-data > a ").each((index, element) => {
      const resultTitle = $(element).children("img");

      const img_url = resultTitle.attr("src");

      const scrapeResult = { img_url };

      scrapeResults.push(scrapeResult);
    });
    return scrapeResults;
  } catch (err) {
    console.error(err);
  }
}

async function scrapeWebsite() {
  const jobsWithHeaders = await scrapeJobHeader();
 console.log(jobsWithHeaders);

}

scrapeWebsite();

但是执行此操作时出现错误“ TypeError：无法读取未定义的属性“替换”：

const img_url = resultTitle.attr("src").replace("images\\/more_color.png","");

返回的图像包括“ images / more_color.png”，但我只想返回实际的产品图像而不是png。

结果看起来像这样：

{ img_url: 'images/more_color.png' },
  { img_url: undefined },
  { img_url: undefined },
  {
    img_url: 'images/20191206/thumb/AK1501-@RH-CRY-LOVE@22X06-825_3L@467400@200@[email protected]'
  },
  { img_url: 'images/more_color.png' },
  { img_url: undefined },
  { img_url: undefined },
  {
    img_url: 'images/20191206/thumb/AK1501-@GD-CRY-LOVE@22X06-825_3L@467399@200@[email protected]'
  },
  { img_url: 'images/more_color.png' },
  { img_url: undefined },
  { img_url: undefined },
  {
    img_url: 'images/20191206/thumb/AK1500-@GD-CRY-QUEEN@3X06-825_3L@467397@200@[email protected]'
  },
  { img_url: 'images/more_color.png' },
  { img_url: undefined },
  { img_url: undefined },

下一步将是摆脱未定义的图像URL，但我还没有走那么远。

Answer 1

此问题的解决方案已发布在https://www.freecodecamp.org/forum/t/web-scraper-outputs-just-one-item-instead-of-many/360427/46