puppeteer.executioncontext.queryobjects.md

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ExecutionContext.queryObjects

ExecutionContext.queryObjects() method

Iterates through the JavaScript heap and finds all the objects with the given prototype.

Signature:

class ExecutionContext {
  queryObjects<Prototype>(
    prototypeHandle: JSHandle<Prototype>
  ): Promise<HandleFor<Prototype[]>>;
}

Parameters

Parameter	Type	Description
prototypeHandle	JSHandle<Prototype>	a handle to the object prototype

Returns:

Promise<HandleFor<Prototype[]>>

A handle to an array of objects with the given prototype.

Example

// Create a Map object
await page.evaluate(() => (window.map = new Map()));
// Get a handle to the Map object prototype
const mapPrototype = await page.evaluateHandle(() => Map.prototype);
// Query all map instances into an array
const mapInstances = await page.queryObjects(mapPrototype);
// Count amount of map objects in heap
const count = await page.evaluate(maps => maps.length, mapInstances);
await mapInstances.dispose();
await mapPrototype.dispose();