puppeteer/website/versioned_docs/version-19.6.0/api/puppeteer.page.evaluate.md
release-please[bot] e13e9647fc
chore: release main (#9501)
🤖 I have created a release *beep* *boop*
---


<details><summary>puppeteer: 19.6.0</summary>

##
[19.6.0](https://github.com/puppeteer/puppeteer/compare/puppeteer-v19.5.2...puppeteer-v19.6.0)
(2023-01-23)


### Miscellaneous Chores

* **puppeteer:** Synchronize puppeteer versions


### Dependencies

* The following workspace dependencies were updated
  * dependencies
    * puppeteer-core bumped from 19.5.2 to 19.6.0
</details>

<details><summary>puppeteer-core: 19.6.0</summary>

##
[19.6.0](https://github.com/puppeteer/puppeteer/compare/puppeteer-core-v19.5.2...puppeteer-core-v19.6.0)
(2023-01-23)


### Features

* **chromium:** roll to Chromium 110.0.5479.0 (r1083080)
([#9500](https://github.com/puppeteer/puppeteer/issues/9500))
([06e816b](06e816bbfa)),
closes [#9470](https://github.com/puppeteer/puppeteer/issues/9470)
* **page:** Adding support for referrerPolicy in `page.goto`
([#9561](https://github.com/puppeteer/puppeteer/issues/9561))
([e3d69ec](e3d69ec554))


### Bug Fixes

* firefox revision resolution should not update chrome revision
([#9507](https://github.com/puppeteer/puppeteer/issues/9507))
([f59bbf4](f59bbf4014)),
closes [#9461](https://github.com/puppeteer/puppeteer/issues/9461)
* improve screenshot method types
([#9529](https://github.com/puppeteer/puppeteer/issues/9529))
([6847f88](6847f8835f))
</details>

---
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Please](https://github.com/googleapis/release-please). See
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Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>
2023-01-23 17:48:02 +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.evaluateHandle` 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();
```