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JSHandle class

Represents an in-page JavaScript object. JSHandles can be created with the page.evaluateHandle method.

Signature:

export declare class JSHandle 

Example

const windowHandle = await page.evaluateHandle(() => window);

JSHandle prevents the referenced JavaScript object from being garbage-collected unless the handle is disposed. 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(), Page.evaluate(), and Page.evaluateHandle().

Constructors

Constructor	Modifiers	Description
(constructor)(context, client, remoteObject)		Constructs a new instance of the JSHandle class

Properties

Property	Modifiers	Type	Description
_client		CDPSession
_context		ExecutionContext
_disposed		boolean
_remoteObject		Protocol.Runtime.RemoteObject

Methods

Method	Modifiers	Description
asElement()		Returns either null or the object handle itself, if the object handle is an instance of ElementHandle.
dispose()		Stops referencing the element handle, and resolves when the object handle is successfully disposed of.
evaluate(pageFunction, args)		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.
evaluateHandle(pageFunction, args)		This method passes this handle as the first argument to pageFunction.
executionContext()		Returns the execution context the handle belongs to.
getProperties()		The method returns a map with property names as keys and JSHandle instances for the property values.
getProperty(propertyName)		Fetches a single property from the referenced object.
jsonValue()		Returns a JSON representation of the object.
toString()		Returns a string representation of the JSHandle.