Page.queryObjects() method

This method iterates the JavaScript heap and finds all objects with the given prototype.

Signature

class Page {
  abstract queryObjects<Prototype>(
    prototypeHandle: JSHandle<Prototype>,
  ): Promise<JSHandle<Prototype[]>>;
}

Parameters

Parameter Type Description
prototypeHandle [JSHandle](./puppeteer.jshandle.md)<Prototype> a handle to the object prototype.

Returns:

Promise<JSHandle<Prototype\[\]>>

Promise which resolves to a handle to an array of objects with this 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();