How to execute a js function on the page while automating in puppeteer?

Question

Say the script has navigated to a certain page. How to execute a js function inside that script?

describe("TestSuite", () => {
  test("Login", async() => {
    await page.goto(APP);
    await page.waitForSelector("[name=loginForm]");
    await page.click("input[name=username]");
    await page.type("input[name=username]", user.username);
    await page.click("input[name=pwd]");
    await page.type("input[name=pwd]", user.pwd);
    await page.click("input[name=login]");
    await page.waitForSelector(".PageBodyVertical");

 // execute a js function x() here which is loaded with the page.

  }, 60000);

Add a click event that calls that function to a button then use `page.click('that_button')` — VTodorov, Jun 04 '18 at 07:51

score 17 · Accepted Answer · answered Jun 04 '18 at 08:07

17

Use the .evaluate() function.

describe("TestSuite", () => {
  test("Login", async() => {
    await page.goto(APP);
    await page.waitForSelector("[name=loginForm]");
    await page.click("input[name=username]");
    await page.type("input[name=username]", user.username);
    await page.click("input[name=pwd]");
    await page.type("input[name=pwd]", user.pwd);
    await page.click("input[name=login]");
    await page.waitForSelector(".PageBodyVertical");

    await page.evaluate( function(){
      x();
    } );

  }, 60000);

answered Jun 04 '18 at 08:07

Pjotr Raskolnikov

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How do you pass a variable into that javascript? – CodeGuru Jun 19 '19 at 05:20
3

@CodeGuru by searching on stackoverflow https://stackoverflow.com/a/46098448/5036031 – Pjotr Raskolnikov Jun 19 '19 at 15:53
await page.evaluate(() => fLogon()); getting undefined flogon on typecript – Sahil Paudel Aug 07 '20 at 20:44
Create fake function from resolve error type script: Ex: function x() { return 'Fake func' } – Jeremias Santos Feb 28 '22 at 17:13

How to execute a js function on the page while automating in puppeteer?

1 Answers1