puppeteer/website/versioned_docs/version-18.1.0/api/puppeteer.frame.waitforfunction.md
release-please[bot] 3aee641c3d
chore(main): release 18.1.0 (#9042)
🤖 I have created a release *beep* *boop*
---


##
[18.1.0](https://github.com/puppeteer/puppeteer/compare/v18.0.5...v18.1.0)
(2022-10-05)


### Features

* **chromium:** roll to Chromium 107.0.5296.0 (r1045629)
([#9039](https://github.com/puppeteer/puppeteer/issues/9039))
([022fbde](022fbde85e))

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---
sidebar_label: Frame.waitForFunction
---
# Frame.waitForFunction() method
**Signature:**
```typescript
class Frame {
waitForFunction<
Params extends unknown[],
Func extends EvaluateFunc<Params> = EvaluateFunc<Params>
>(
pageFunction: Func | string,
options?: FrameWaitForFunctionOptions,
...args: Params
): Promise<HandleFor<Awaited<ReturnType<Func>>>>;
}
```
## Parameters
| Parameter | Type | Description |
| ------------ | ------------------------------------------------------------------------- | ---------------------------------------------------------------------- |
| pageFunction | Func \| string | the function to evaluate in the frame context. |
| options | [FrameWaitForFunctionOptions](./puppeteer.framewaitforfunctionoptions.md) | <i>(Optional)</i> options to configure the polling method and timeout. |
| args | Params | arguments to pass to the <code>pageFunction</code>. |
**Returns:**
Promise&lt;[HandleFor](./puppeteer.handlefor.md)&lt;Awaited&lt;ReturnType&lt;Func&gt;&gt;&gt;&gt;
the promise which resolve when the `pageFunction` returns a truthy value.
## Example
The `waitForFunction` can be used to observe viewport size change:
```ts
const puppeteer = require('puppeteer');
(async () => {
. const browser = await puppeteer.launch();
. const page = await browser.newPage();
. const watchDog = page.mainFrame().waitForFunction('window.innerWidth < 100');
. page.setViewport({width: 50, height: 50});
. await watchDog;
. await browser.close();
})();
```
To pass arguments from Node.js to the predicate of `page.waitForFunction` function:
```ts
const selector = '.foo';
await frame.waitForFunction(
selector => !!document.querySelector(selector),
{}, // empty options object
selector
);
```