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---
id: class-jshandle
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title: "JSHandle"
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---
JSHandle represents an in-page JavaScript object. JSHandles can be created with the [page.evaluateHandle(pageFunction[, arg])](api/class-page.md#pageevaluatehandlepagefunction -arg) method.
```js
const windowHandle = await page.evaluateHandle(() => window);
// ...
```
JSHandle prevents the referenced JavaScript object being garbage collected unless the handle is exposed with [jsHandle.dispose() ](api/class-jshandle.md#jshandledispose ). JSHandles are auto-disposed when their origin frame gets navigated or the parent context gets destroyed.
JSHandle instances can be used as an argument in [page.$eval(selector, pageFunction[, arg])](api/class-page.md#pageevalselector -pagefunction-arg), [page.evaluate(pageFunction[, arg])](api/class-page.md#pageevaluatepagefunction -arg) and [page.evaluateHandle(pageFunction[, arg])](api/class-page.md#pageevaluatehandlepagefunction -arg) methods.
- [jsHandle.asElement() ](api/class-jshandle.md#jshandleaselement )
- [jsHandle.dispose() ](api/class-jshandle.md#jshandledispose )
- [jsHandle.evaluate(pageFunction[, arg])](api/class-jshandle.md#jshandleevaluatepagefunction -arg)
- [jsHandle.evaluateHandle(pageFunction[, arg])](api/class-jshandle.md#jshandleevaluatehandlepagefunction -arg)
- [jsHandle.getProperties() ](api/class-jshandle.md#jshandlegetproperties )
- [jsHandle.getProperty(propertyName) ](api/class-jshandle.md#jshandlegetpropertypropertyname )
- [jsHandle.jsonValue() ](api/class-jshandle.md#jshandlejsonvalue )
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## jsHandle.asElement()
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- returns: < [null]|[ElementHandle]>
Returns either `null` or the object handle itself, if the object handle is an instance of [ElementHandle].
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## jsHandle.dispose()
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- returns: < [Promise]>
The `jsHandle.dispose` method stops referencing the element handle.
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## jsHandle.evaluate(pageFunction[, arg])
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- `pageFunction` < [function]> Function to be evaluated in browser context
- `arg` < [EvaluationArgument]> Optional argument to pass to `pageFunction`
- returns: < [Promise]< [Serializable]>>
Returns the return value of `pageFunction`
This method passes this handle as the first argument to `pageFunction` .
If `pageFunction` returns a [Promise], then `handle.evaluate` would wait for the promise to resolve and return its value.
Examples:
```js
const tweetHandle = await page.$('.tweet .retweets');
expect(await tweetHandle.evaluate((node, suffix) => node.innerText, ' retweets')).toBe('10 retweets');
```
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## jsHandle.evaluateHandle(pageFunction[, arg])
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- `pageFunction` < [function]|[string]> Function to be evaluated
- `arg` < [EvaluationArgument]> Optional argument to pass to `pageFunction`
- returns: < [Promise]< [JSHandle]>>
Returns the return value of `pageFunction` as in-page object (JSHandle).
This method passes this handle as the first argument to `pageFunction` .
The only difference between `jsHandle.evaluate` and `jsHandle.evaluateHandle` is that `jsHandle.evaluateHandle` returns in-page object (JSHandle).
If the function passed to the `jsHandle.evaluateHandle` returns a [Promise], then `jsHandle.evaluateHandle` would wait for the promise to resolve and return its value.
See [page.evaluateHandle(pageFunction[, arg])](api/class-page.md#pageevaluatehandlepagefunction -arg) for more details.
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## jsHandle.getProperties()
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- returns: < [Promise]< [Map]< [string], [JSHandle]>>>
The method returns a map with **own property names** as keys and JSHandle instances for the property values.
```js
const handle = await page.evaluateHandle(() => ({window, document}));
const properties = await handle.getProperties();
const windowHandle = properties.get('window');
const documentHandle = properties.get('document');
await handle.dispose();
```
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## jsHandle.getProperty(propertyName)
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- `propertyName` < [string]> property to get
- returns: < [Promise]< [JSHandle]>>
Fetches a single property from the referenced object.
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## jsHandle.jsonValue()
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- returns: < [Promise]< [Serializable]>>
Returns a JSON representation of the object. If the object has a `toJSON` function, it **will not be called** .
> **NOTE** The method will return an empty JSON object if the referenced object is not stringifiable. It will throw an error if the object has circular references.
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[Playwright]: api/class-playwright.md "Playwright"
[Browser]: api/class-browser.md "Browser"
[BrowserContext]: api/class-browsercontext.md "BrowserContext"
[Page]: api/class-page.md "Page"
[Frame]: api/class-frame.md "Frame"
[ElementHandle]: api/class-elementhandle.md "ElementHandle"
[JSHandle]: api/class-jshandle.md "JSHandle"
[ConsoleMessage]: api/class-consolemessage.md "ConsoleMessage"
[Dialog]: api/class-dialog.md "Dialog"
[Download]: api/class-download.md "Download"
[Video]: api/class-video.md "Video"
[FileChooser]: api/class-filechooser.md "FileChooser"
[Keyboard]: api/class-keyboard.md "Keyboard"
[Mouse]: api/class-mouse.md "Mouse"
[Touchscreen]: api/class-touchscreen.md "Touchscreen"
[Request]: api/class-request.md "Request"
[Response]: api/class-response.md "Response"
[Selectors]: api/class-selectors.md "Selectors"
[Route]: api/class-route.md "Route"
[WebSocket]: api/class-websocket.md "WebSocket"
[TimeoutError]: api/class-timeouterror.md "TimeoutError"
[Accessibility]: api/class-accessibility.md "Accessibility"
[Worker]: api/class-worker.md "Worker"
[BrowserServer]: api/class-browserserver.md "BrowserServer"
[BrowserType]: api/class-browsertype.md "BrowserType"
[Logger]: api/class-logger.md "Logger"
[ChromiumBrowser]: api/class-chromiumbrowser.md "ChromiumBrowser"
[ChromiumBrowserContext]: api/class-chromiumbrowsercontext.md "ChromiumBrowserContext"
[ChromiumCoverage]: api/class-chromiumcoverage.md "ChromiumCoverage"
[CDPSession]: api/class-cdpsession.md "CDPSession"
[FirefoxBrowser]: api/class-firefoxbrowser.md "FirefoxBrowser"
[WebKitBrowser]: api/class-webkitbrowser.md "WebKitBrowser"
[Array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array "Array"
[Buffer]: https://nodejs.org/api/buffer.html#buffer_class_buffer "Buffer"
[ChildProcess]: https://nodejs.org/api/child_process.html "ChildProcess"
[Element]: https://developer.mozilla.org/en-US/docs/Web/API/element "Element"
[Error]: https://nodejs.org/api/errors.html#errors_class_error "Error"
[Evaluation Argument]: ./core-concepts.md#evaluationargument "Evaluation Argument"
[Map]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map "Map"
[Object]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object "Object"
[Promise]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise "Promise"
[RegExp]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp "RegExp"
[Serializable]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#Description "Serializable"
[UIEvent.detail]: https://developer.mozilla.org/en-US/docs/Web/API/UIEvent/detail "UIEvent.detail"
[URL]: https://nodejs.org/api/url.html "URL"
[USKeyboardLayout]: ../src/usKeyboardLayout.ts "USKeyboardLayout"
[UnixTime]: https://en.wikipedia.org/wiki/Unix_time "Unix Time"
[boolean]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type "Boolean"
[function]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function "Function"
[iterator]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols "Iterator"
[null]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/null "null"
[number]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type "Number"
[origin]: https://developer.mozilla.org/en-US/docs/Glossary/Origin "Origin"
[selector]: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Selectors "selector"
[Readable]: https://nodejs.org/api/stream.html#stream_class_stream_readable "Readable"
[string]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type "string"
[xpath]: https://developer.mozilla.org/en-US/docs/Web/XPath "xpath"