puppeteer/website/versioned_docs/version-19.4.0/api/puppeteer.page.evaluate.md
release-please[bot] 931d4fced5
chore: release main (#9322)
🤖 I have created a release *beep* *boop*
---


<details><summary>puppeteer: 19.4.0</summary>

##
[19.4.0](https://github.com/puppeteer/puppeteer/compare/puppeteer-v19.3.0...puppeteer-v19.4.0)
(2022-12-07)


### Features

* **chromium:** roll to Chromium 109.0.5412.0 (r1069273)
([#9364](https://github.com/puppeteer/puppeteer/issues/9364))
([1875da6](1875da6191)),
closes [#9233](https://github.com/puppeteer/puppeteer/issues/9233)


### Dependencies

* The following workspace dependencies were updated
  * dependencies
    * puppeteer-core bumped from 19.3.0 to 19.4.0
</details>

<details><summary>puppeteer-core: 19.4.0</summary>

##
[19.4.0](https://github.com/puppeteer/puppeteer/compare/puppeteer-core-v19.3.0...puppeteer-core-v19.4.0)
(2022-12-07)


### Features

* ability to send headers via ws connection to browser in node.js
environment
([#9314](https://github.com/puppeteer/puppeteer/issues/9314))
([937fffa](937fffaedc)),
closes [#7218](https://github.com/puppeteer/puppeteer/issues/7218)
* **chromium:** roll to Chromium 109.0.5412.0 (r1069273)
([#9364](https://github.com/puppeteer/puppeteer/issues/9364))
([1875da6](1875da6191)),
closes [#9233](https://github.com/puppeteer/puppeteer/issues/9233)
* **puppeteer-core:** keydown supports commands
([#9357](https://github.com/puppeteer/puppeteer/issues/9357))
([b7ebc5d](b7ebc5d9bb))


### Bug Fixes

* **puppeteer-core:** avoid type instantiation errors
([#9370](https://github.com/puppeteer/puppeteer/issues/9370))
([17f31a9](17f31a9ee4)),
closes [#9369](https://github.com/puppeteer/puppeteer/issues/9369)
</details>

---
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Please](https://github.com/googleapis/release-please). See
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2022-12-07 19:35:29 +01:00

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---
sidebar_label: Page.evaluate
---
# Page.evaluate() method
Evaluates a function in the page's context and returns the result.
If the function passed to `page.evaluteHandle` returns a Promise, the function will wait for the promise to resolve and return its value.
#### Signature:
```typescript
class Page {
evaluate<
Params extends unknown[],
Func extends EvaluateFunc<Params> = EvaluateFunc<Params>
>(
pageFunction: Func | string,
...args: Params
): Promise<Awaited<ReturnType<Func>>>;
}
```
## Parameters
| Parameter | Type | Description |
| ------------ | -------------- | ------------------------------------------ |
| pageFunction | Func \| string | a function that is run within the page |
| args | Params | arguments to be passed to the pageFunction |
**Returns:**
Promise&lt;Awaited&lt;ReturnType&lt;Func&gt;&gt;&gt;
the return value of `pageFunction`.
## Example 1
```ts
const result = await frame.evaluate(() => {
return Promise.resolve(8 * 7);
});
console.log(result); // prints "56"
```
You can pass a string instead of a function (although functions are recommended as they are easier to debug and use with TypeScript):
## Example 2
```ts
const aHandle = await page.evaluate('1 + 2');
```
To get the best TypeScript experience, you should pass in as the generic the type of `pageFunction`:
```ts
const aHandle = await page.evaluate(() => 2);
```
## Example 3
[ElementHandle](./puppeteer.elementhandle.md) instances (including [JSHandle](./puppeteer.jshandle.md)s) can be passed as arguments to the `pageFunction`:
```ts
const bodyHandle = await page.$('body');
const html = await page.evaluate(body => body.innerHTML, bodyHandle);
await bodyHandle.dispose();
```