puppeteer/website/versioned_docs/version-9.1.1/puppeteer.jshandle.md
2021-08-10 11:09:48 +01:00

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[Home](./index.md) &gt; [puppeteer](./puppeteer.md) &gt; [JSHandle](./puppeteer.jshandle.md)
## JSHandle class
Represents an in-page JavaScript object. JSHandles can be created with the [page.evaluateHandle](./puppeteer.page.evaluatehandle.md) method.
<b>Signature:</b>
```typescript
export declare class JSHandle<HandleObjectType = unknown>
```
## Remarks
The constructor for this class is marked as internal. Third-party code should not call the constructor directly or create subclasses that extend the `JSHandle` class.
## Example
```js
const windowHandle = await page.evaluateHandle(() => window);
```
JSHandle prevents the referenced JavaScript object from being garbage-collected unless the handle is [disposed](./puppeteer.jshandle.dispose.md). JSHandles are auto- disposed when their origin frame gets navigated or the parent context gets destroyed.
JSHandle instances can be used as arguments for [Page.$eval()](./puppeteer.page._eval.md), [Page.evaluate()](./puppeteer.page.evaluate.md), and [Page.evaluateHandle()](./puppeteer.page.evaluatehandle.md).
## Methods
| Method | Modifiers | Description |
| --- | --- | --- |
| [asElement()](./puppeteer.jshandle.aselement.md) | | |
| [dispose()](./puppeteer.jshandle.dispose.md) | | Stops referencing the element handle, and resolves when the object handle is successfully disposed of. |
| [evaluate(pageFunction, args)](./puppeteer.jshandle.evaluate.md) | | This method passes this handle as the first argument to <code>pageFunction</code>. If <code>pageFunction</code> returns a Promise, then <code>handle.evaluate</code> would wait for the promise to resolve and return its value. |
| [evaluateHandle(pageFunction, args)](./puppeteer.jshandle.evaluatehandle.md) | | This method passes this handle as the first argument to <code>pageFunction</code>. |
| [executionContext()](./puppeteer.jshandle.executioncontext.md) | | Returns the execution context the handle belongs to. |
| [getProperties()](./puppeteer.jshandle.getproperties.md) | | The method returns a map with property names as keys and JSHandle instances for the property values. |
| [getProperty(propertyName)](./puppeteer.jshandle.getproperty.md) | | Fetches a single property from the referenced object. |
| [jsonValue()](./puppeteer.jshandle.jsonvalue.md) | | |
| [toString()](./puppeteer.jshandle.tostring.md) | | Returns a string representation of the JSHandle. |