How to execute JavaScript on a page with Puppeteer?

To execute JavaScript on a page with Puppeteer, you can use the page.evaluate() function. Here's an example of how to use this function:

First, you need to create a new Puppeteer browser instance:

const puppeteer = require('puppeteer');

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

  // Your code to execute JavaScript on the page will go here

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

Then, you can use the page.evaluate() function to execute JavaScript on the page. For example, if you want to change the background color of the page:

await page.evaluate(() => {
  document.body.style.backgroundColor = 'lightblue';
});

You can also pass arguments to the JavaScript code inside page.evaluate() by providing them as additional arguments to the function:

const color = 'lightblue';

await page.evaluate(color => {
  document.body.style.backgroundColor = color;
}, color);

Finally, make sure to call browser.close() to close the Puppeteer browser instance once you're done executing your JavaScript code.

With these steps, you can execute JavaScript on a page with Puppeteer.