puppeteer/website/versioned_docs/version-15.3.2/api/puppeteer.executioncontext.queryobjects.md
release-please[bot] dd27559090
chore(main): release 15.3.2 (#8647)
* chore(main): release 15.3.2

* chore: generate versioned docs

Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>
2022-07-08 09:58:30 +02:00

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---
sidebar_label: ExecutionContext.queryObjects
---
# ExecutionContext.queryObjects() method
This method iterates the JavaScript heap and finds all the objects with the given prototype.
**Signature:**
```typescript
class ExecutionContext {
queryObjects<Prototype>(
prototypeHandle: JSHandle<Prototype>
): Promise<HandleFor<Prototype[]>>;
}
```
## Parameters
| Parameter | Type | Description |
| --------------- | ---------------------------------------------------- | -------------------------------- |
| prototypeHandle | [JSHandle](./puppeteer.jshandle.md)&lt;Prototype&gt; | a handle to the object prototype |
**Returns:**
Promise&lt;[HandleFor](./puppeteer.handlefor.md)&lt;Prototype\[\]&gt;&gt;
A handle to an array of objects with the given prototype.
## Remarks
## Example
```ts
// 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();
```