类似于 Puppeteer 中的 document.ready() 的功能？

Question

Puppeteer中是否有类似document.ready()的内容？

有：

page.waitForSelector(selector)

既然任何一个HTML页面上都有那么多同名选择器，这个函数怎么能确定加载了正确的页面呢？这是一个简单的功能，但我在 page.content() 之前使用它时导致了很多错误。我不确定这个功能遗漏了什么。

Answer 1

您可以使用page.waitForNavigation() as an alternative to jQuery's document.ready()函数：

await page.waitForNavigation({waitUntil: 'load'});             // consider navigation to be finished when the load event is fired.
await page.waitForNavigation({waitUntil: 'domcontentloaded'}); // consider navigation to be finished when the DOMContentLoaded event is fired.
await page.waitForNavigation({waitUntil: 'networkidle0'});     // consider navigation to be finished when there are no more than 0 network connections for at least 500 ms.
await page.waitForNavigation({waitUntil: 'networkidle2'});     // consider navigation to be finished when there are no more than 2 network connections for at least 500 ms.

或者，您可以使用 page.goto() 中的 waitUntil 选项等待文档加载：

await page.goto('https://example.com/', {waitUntil: 'load'});
await page.goto('https://example.com/', {waitUntil: 'domcontentloaded'});
await page.goto('https://example.com/', {waitUntil: 'networkidle0'});
await page.goto('https://example.com/', {waitUntil: 'networkidle2'});

Answer 2

有时 waitForNavigation 只是超时。我想出了使用 waitForFunction 的其他解决方案，检查文档是否处于就绪状态。

await page.waitForFunction(() => document.readyState === "complete");