Puppeteer 选择链接 [英] Puppeteer Select Link

问题描述

我想单击 html 页面中的链接，其中包含以下代码段:

I want to click on a link in a html page, which contains following snippet:

<p>Die maximale Trefferanzahl von 200 wurde überschritten.
  <a href="/rp_web/search.do?doppelt">Verdoppeln Sie hier  Suchergebnislimit.</a>
</p>

我之前设置了一些过滤器，然后我正在加载页面，这将加载我需要的页面.在结果页面上，我想单击 html 代码段中的链接.我正在尝试使用的 js 是这个

I'm setting some filters before and then I am loading the page, which loads the page I need. On that resulting page, I want to click on the link as seen in the html snippet. The js I'm trying to use is this one

await Promise.all([
    page.click('input#landNW'), // set a filter
    page.click('input[type=submit]'), // submit the form
    page.waitForNavigation(), // wait for the page to load
    page.click('p a'), // not working: double the search results
    page.waitForNavigation() // not working: waiting for the page to reload
]).catch(e => console.log(e)); // no error

我很确定 page.click('p a') 工作正常，因为在我的 chrome 浏览器的控制台中，我可以执行 document.querySelector("pa").click()，然后按预期重新加载页面.

I am pretty sure the page.click('p a') is working properly, because in the console of my chrome browser I can do document.querySelector("p a").click(), which then reloads the page as expected.

我还尝试使用 href attr 来选择网址，例如使用 page.click('a[href="/rp_web/search.do?doppelt"]')，但出现错误:没有找到选择器的节点:a[href="/rp_web/search.do?doppelt"].

I have also tried to select the url by using the href attr, e.g. with page.click('a[href="/rp_web/search.do?doppelt"]'), but I got an error: No node found for selector: a[href="/rp_web/search.do?doppelt"].

我怎样才能完成我期望发生的事情?

How can I accomplish what I expect to happen?

编辑您可以在此处找到完整的存储库:bitbucket/ytNeskews

EDIT You can find the complete repo here: bitbucket/ytNeskews

推荐答案

有很多关于 page.click 不工作的报告，在您的情况下，由于某种原因它确实不会工作.幸运的是，我们可以在旧的 page.evaluate(或 page.$eval)的帮助下完成所有操作:这里我在浏览器上下文中手动单击链接:

There are lots of reports about page.click not working and in your case it indeed won't work for some reason. Luckily we can do everything with the help of a good old page.evaluate (or page.$eval): here I'm clicking the link manually in the browser context:

const puppeteer  = require ('puppeteer');
(async () => {
    const browser = await puppeteer.launch({ headless : false });
    const page = await browser.newPage();
    await page.goto('https://www.handelsregister.de/rp_web/mask.do?Typ=e');

    await Promise.all([
        page.click('input#landNW'), // set a filter
        page.click('input[type=submit]'), // submit the form
        page.waitForNavigation(), // wait for the page to load
    ]).catch(e => console.log(e));

    // Print the number of allowed results (must be 200)
    console.log(await page.$eval('#inhalt p', el => el.textContent.match(/\d+ hits/)[0]));

    await Promise.all([
         // Manual clicking of the link
         page.$eval('p a', el => el.click()),
         page.waitForNavigation()
    ]).catch(e => console.log(e));

    // Print the number of allowed results (must be 400 now)
    console.log(await page.$eval('#inhalt p', el => el.textContent.match(/\d+ hits/)[0]));

    await browser.close();
})();

结果:

200 次点击
400 次点击

200 hits
400 hits

也不是说您应该一次只等待一个页面导航.如果可以的话，还有一个注意事项 - 在 Chromium 可见 ({headless : false}) 的情况下编写此类脚本要方便得多.

Also not that you should wait only for one page navigation at once. And one more note if I may — it is much more convenient to write such scripts with Chromium visible ({headless : false}).

这篇关于Puppeteer 选择链接的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！