69 lines
2.3 KiB
Markdown
69 lines
2.3 KiB
Markdown
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<!-- Do not edit this file. It is automatically generated by API Documenter. -->
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[Home](./index.md) > [puppeteer](./puppeteer.md) > [Page](./puppeteer.page.md) > [evaluateHandle](./puppeteer.page.evaluatehandle.md)
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## Page.evaluateHandle() method
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<b>Signature:</b>
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```typescript
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evaluateHandle<HandlerType extends JSHandle = JSHandle>(pageFunction: EvaluateHandleFn, ...args: SerializableOrJSHandle[]): Promise<HandlerType>;
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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 | [EvaluateHandleFn](./puppeteer.evaluatehandlefn.md) | a function that is run within the page |
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| args | [SerializableOrJSHandle](./puppeteer.serializableorjshandle.md)\[\] | arguments to be passed to the pageFunction |
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<b>Returns:</b>
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Promise<HandlerType>
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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.evaluteHandle` 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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```
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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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```
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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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```
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const button = await page.evaluateHandle(() => document.querySelector('button'));
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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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```
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const button = await page.evaluateHandle<ElementHandle>(...);
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```
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