74 lines
2.3 KiB
Markdown
74 lines
2.3 KiB
Markdown
---
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sidebar_label: Page.evaluateHandle
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---
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# Page.evaluateHandle() method
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#### Signature:
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```typescript
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class Page {
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evaluateHandle<
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Params extends unknown[],
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Func extends EvaluateFunc<Params> = EvaluateFunc<Params>,
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>(
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pageFunction: Func | string,
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...args: Params
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): Promise<HandleFor<Awaited<ReturnType<Func>>>>;
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}
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```
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## Parameters
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| Parameter | Type | Description |
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| ------------ | -------------- | ------------------------------------------ |
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| pageFunction | Func \| string | a function that is run within the page |
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| args | Params | arguments to be passed to the pageFunction |
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**Returns:**
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Promise<[HandleFor](./puppeteer.handlefor.md)<Awaited<ReturnType<Func>>>>
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## Remarks
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The only difference between [page.evaluate](./puppeteer.page.evaluate.md) and `page.evaluateHandle` is that `evaluateHandle` will return the value wrapped in an in-page object.
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If the function passed to `page.evaluateHandle` returns a Promise, the function will wait for the promise to resolve and return its value.
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You can pass a string instead of a function (although functions are recommended as they are easier to debug and use with TypeScript):
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## Example 1
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```ts
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const aHandle = await page.evaluateHandle('document');
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```
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## Example 2
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[JSHandle](./puppeteer.jshandle.md) instances can be passed as arguments to the `pageFunction`:
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```ts
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const aHandle = await page.evaluateHandle(() => document.body);
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const resultHandle = await page.evaluateHandle(body => body.innerHTML, aHandle);
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console.log(await resultHandle.jsonValue());
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await resultHandle.dispose();
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```
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Most of the time this function returns a [JSHandle](./puppeteer.jshandle.md), but if `pageFunction` returns a reference to an element, you instead get an [ElementHandle](./puppeteer.elementhandle.md) back:
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## Example 3
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```ts
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const button = await page.evaluateHandle(() =>
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document.querySelector('button')
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);
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// can call `click` because `button` is an `ElementHandle`
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await button.click();
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```
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The TypeScript definitions assume that `evaluateHandle` returns a `JSHandle`, but if you know it's going to return an `ElementHandle`, pass it as the generic argument:
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```ts
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const button = await page.evaluateHandle<ElementHandle>(...);
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```
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