puppeteer/docs/api/puppeteer.jshandle.md
2024-04-29 14:50:39 +02:00

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---
sidebar_label: JSHandle
---
# JSHandle class
Represents a reference to a JavaScript object. Instances can be created using [Page.evaluateHandle()](./puppeteer.page.evaluatehandle.md).
Handles prevent the referenced JavaScript object from being garbage-collected unless the handle is purposely [disposed](./puppeteer.jshandle.dispose.md). JSHandles are auto-disposed when their associated frame is navigated away or the parent context gets destroyed.
Handles can be used as arguments for any evaluation function such as [Page.$eval()](./puppeteer.page._eval.md), [Page.evaluate()](./puppeteer.page.evaluate.md), and [Page.evaluateHandle()](./puppeteer.page.evaluatehandle.md). They are resolved to their referenced object.
#### Signature:
```typescript
export declare abstract class JSHandle<T = 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
```ts
const windowHandle = await page.evaluateHandle(() => window);
```
## Properties
<table><thead><tr><th>
Property
</th><th>
Modifiers
</th><th>
Type
</th><th>
Description
</th></tr></thead>
<tbody><tr><td>
<span id="_">\_</span>
</td><td>
`optional`
</td><td>
T
</td><td>
Used for nominally typing [JSHandle](./puppeteer.jshandle.md).
</td></tr>
<tr><td>
<span id="move">move</span>
</td><td>
</td><td>
() =&gt; this
</td><td>
</td></tr>
</tbody></table>
## Methods
<table><thead><tr><th>
Method
</th><th>
Modifiers
</th><th>
Description
</th></tr></thead>
<tbody><tr><td>
<span id="aselement">[asElement()](./puppeteer.jshandle.aselement.md)</span>
</td><td>
</td><td>
Either `null` or the handle itself if the handle is an instance of [ElementHandle](./puppeteer.elementhandle.md).
</td></tr>
<tr><td>
<span id="dispose">[dispose()](./puppeteer.jshandle.dispose.md)</span>
</td><td>
</td><td>
Releases the object referenced by the handle for garbage collection.
</td></tr>
<tr><td>
<span id="evaluate">[evaluate(pageFunction, args)](./puppeteer.jshandle.evaluate.md)</span>
</td><td>
</td><td>
Evaluates the given function with the current handle as its first argument.
</td></tr>
<tr><td>
<span id="evaluatehandle">[evaluateHandle(pageFunction, args)](./puppeteer.jshandle.evaluatehandle.md)</span>
</td><td>
</td><td>
Evaluates the given function with the current handle as its first argument.
</td></tr>
<tr><td>
<span id="getproperties">[getProperties()](./puppeteer.jshandle.getproperties.md)</span>
</td><td>
</td><td>
Gets a map of handles representing the properties of the current handle.
</td></tr>
<tr><td>
<span id="getproperty">[getProperty(propertyName)](./puppeteer.jshandle.getproperty.md)</span>
</td><td>
</td><td>
Fetches a single property from the referenced object.
</td></tr>
<tr><td>
<span id="getproperty">[getProperty(propertyName)](./puppeteer.jshandle.getproperty_1.md)</span>
</td><td>
</td><td>
</td></tr>
<tr><td>
<span id="jsonvalue">[jsonValue()](./puppeteer.jshandle.jsonvalue.md)</span>
</td><td>
</td><td>
A vanilla object representing the serializable portions of the referenced object.
**Remarks:**
If the object has a `toJSON` function, it **will not** be called.
</td></tr>
<tr><td>
<span id="remoteobject">[remoteObject()](./puppeteer.jshandle.remoteobject.md)</span>
</td><td>
</td><td>
Provides access to the [Protocol.Runtime.RemoteObject](https://chromedevtools.github.io/devtools-protocol/tot/Runtime/#type-RemoteObject) backing this handle.
</td></tr>
<tr><td>
<span id="tostring">[toString()](./puppeteer.jshandle.tostring.md)</span>
</td><td>
</td><td>
Returns a string representation of the JSHandle.
**Remarks:**
Useful during debugging.
</td></tr>
</tbody></table>