how to use document.getElementById() in Nodejs

问题:

i'm trying to get elements by id from an html file in a js file using nodejs. I'm getting the error 'document id not defined' because node doesn't provide a document object model by default.

So how can i use document.getElementById() in nodejs ?

Thank you !

回答1:

If you want to parse files within the same server you should probably use some of this options, because nodejs it's just a JavaScript implementation, There is no window or document object, see this. But to answer exactly your question:

how can I use document.getElementById() in nodejs ?

You could do it using Puppeteer

Puppeteer is a Node library which provides a high-level API to control headless Chrome or Chromium over the DevTools Protocol. It can also be configured to use full (non-headless) Chrome or Chromium.

Here a basic example:

const puppeteer = require('puppeteer');

(async () => {
    const browser = await puppeteer.launch();


        page = await browser.newPage();
        await page.goto('http://example.com/some.html', {waitUntil: 'load'});


    const newPage = await page.evaluate(() => {

        return  document.getElementById("idexample").innerHTML;

        });

     console.log(newPage)

  })();

回答2:

Use JSDOM npm package:

jsdom is a pure-JavaScript implementation of many web standards, notably the WHATWG DOM and HTML Standards, for use with Node.js. In general, the goal of the project is to emulate enough of a subset of a web browser to be useful for testing and scraping real-world web applications. https://github.com/jsdom/jsdom