错误：未能找到 <img data-src="url> 的元素匹配选择器

Question

在 Puppeteer 上运行，全部更新。

预期的过程是转到网站，其中 url 是 url/{search item} 并遍历搜索名称列表。然后对于每个搜索项 --> 搜索页面，获取每个列表的名称、价格和图像 url。现在出现错误，找不到选择器。感谢您对此的任何帮助，非常感谢！

网站数据布局如下：

<div class="items-box-content">
   <section class="items-box">
      <a href="https://listingurl">
         <figure class="items-box-photo">
            <img data-src="https://imageurl.jpg" class=" lazyloaded" src="https://imageurl.jpg">
         </figure>
         <div class="items-box-main">
            <h3 class="items-box-name"> listing name </h3>

            <div class="items-box-figure">
               <div class="items-price font-4"> $29.95 </div> // item's price
            </h3>
         </div>

而我现在拥有的是（引发错误）：

const puppeteer = require('puppeteer');
const searches = ["a", "b", "c"]; //appended to url
(async () => {
   const browser = await puppeteer.launch({ headless: false });
   let results =[];
   for (const search of searches) {
         try {
            page = await browser.newPage();
            await page.goto(`https://weburl/?keyword=${search}`);
            await page.evaluate(() => { document.querySelector('div[class*="items-box"]').scrollIntoView();});
            let elements = await page.$$('div[class*="items-box"]');
            for (let element of elements) {
               let listImg = await element.$eval(('img[class="items-box-photo]'), img => img.getAttribute('src'));
               let listTitle = await element.$eval(('d[class="items-box-main"] > h[class="items-box-name"]'), node => node.innerText.trim());
               let listPrice = await element.$eval(('d[class="items-box-figure"] > d[class="items-price"]'), node => node.innerText.trim());
               let listUrl = await element.$eval(('d[class="items-box-content"] > a[class*="items-box"]'), node => node.getAttribute('href'));

               results.push({ 
                  listImg, 
                  listTitle, 
                  listPrice, 
                  listUrl 
               })
               return results;
            }
         } finally {
            await page.close
         }
   }
})();

抛出的错误是

（节点：5168）UnhandledPromiseRejectionWarning：错误：错误：未能 查找匹配选择器“img[class="items-box-photo]”的元素

Answer 1

问题就在错误消息中 (Error: failed to find element matching selector ...)。

选择器在以下几行中是错误的：

let listImg = await element.$eval(('img[class="items-box-photo]'), img => img.getAttribute('src'));
let listTitle = await element.$eval(('d[class="items-box-main"] > h[class="items-box-name"]'), node => node.innerText.trim());
let listPrice = await element.$eval(('d[class="items-box-figure"] > d[class="items-price"]'), node => node.innerText.trim());
let listUrl = await element.$eval(('d[class="items-box-content"] > a[class*="items-box"]'), node => node.getAttribute('href'));

根据你给出的 HTML 代码，这些应该是：

let listImg = await element.$eval('img.lazyloaded', img => img.getAttribute('src'));
let listTitle = await element.$eval('h3.items-box-name', node => node.innerText.trim());
let listPrice = await element.$eval('div.items-price', node => node.innerText.trim());
let listUrl = await element.$eval('div.items-box-content a', node => node.getAttribute('href'));

注意，查询类的正确方法不是使用[class=...]，而是使用class selector：.

Answer 2

我用我的测试/调试更新了你的代码。

const puppeteer = require('puppeteer');

const searches = ["a"];

(async () => {

    const browser = await puppeteer.launch({ headless: false });

    function delay(timeout) {
        return new Promise((resolve) => {
            setTimeout(resolve, timeout);
        });
    }

    let results = [];

    for (const search of searches) {

        try {
            page = await browser.newPage();
            await page.goto(`https:url/`);

            await page.evaluate(() => { document.querySelector('section[class*="items-box"]').scrollIntoView(); });

            let elements = await page.$$('section[class*="items-box"]');
            console.log(elements.length)
            console.log('wait 6  seconds')
            await delay(6000);

            for (let element of elements) {
                // await delay(6000);

                let listImg = await element.$eval(('img'), img => img.getAttribute('src'));
                let listTitle = await element.$eval(('h3[class="items-box-name font-2"]'), node => node.innerText.trim());
                let listPrice = await element.$eval(('div[class="items-box-price font-5"]'), node => node.innerText.trim());
                let listUrl = await element.$eval(('div[class="items-box-content clearfix"] a'), node => node.getAttribute('href'));

                results.push({
                    listImg,
                    listTitle,
                    listPrice,
                    listUrl
                });
            }

            debugger;

        } catch (error) {
            console.log(error)
        } finally {
            //await page.close
            await browser.close
        }
    }
    console.log(results)
    return results;
})();

---

更新内容：
1. return result 在for 循环中

for(){
   return result;
}

=>

for(){

}
return result;

1. 更新querySelector

section[class*="items-box"]

img  // There is only one img tags in "element"

h3[class="items-box-name font-2"]  // removed outer 'element'

div[class="items-box-figure"] > div[class="items-price font-4"]

div[class="items-box-price font-5  // updated class name? on my side 

items-box-price

div[class="items-box-content clearfix"] a 

1. 更新睡眠持续时间 6 秒，这是相对网络速度（网络加载持续时间）。

2. trycatchfinally
catch帮助您处理下一步，尽管一步崩溃。