puppeteer/docs/api/puppeteer.webworker.evaluatehandle.md

41 lines
1.3 KiB
Markdown
Raw Normal View History

2022-07-05 13:41:43 +00:00
---
sidebar_label: WebWorker.evaluateHandle
---
# WebWorker.evaluateHandle() method
Evaluates a given function in the [worker](./puppeteer.webworker.md).
2022-07-05 13:41:43 +00:00
#### Signature:
2022-07-05 13:41:43 +00:00
```typescript
class WebWorker {
evaluateHandle<
Params extends unknown[],
Func extends EvaluateFunc<Params> = EvaluateFunc<Params>,
2022-07-05 13:41:43 +00:00
>(
func: Func | string,
2022-07-05 13:41:43 +00:00
...args: Params
): Promise<HandleFor<Awaited<ReturnType<Func>>>>;
}
```
## Parameters
| Parameter | Type | Description |
| --------- | -------------- | ----------------------------------------- |
| func | Func \| string | Function to be evaluated. |
| args | Params | Arguments to pass into <code>func</code>. |
2022-07-05 13:41:43 +00:00
**Returns:**
Promise&lt;[HandleFor](./puppeteer.handlefor.md)&lt;Awaited&lt;ReturnType&lt;Func&gt;&gt;&gt;&gt;
A [handle](./puppeteer.jshandle.md) to the return value of `func`.
## Remarks
If the given function returns a promise, [evaluate](./puppeteer.webworker.evaluate.md) will wait for the promise to resolve.
In general, you should use [evaluateHandle](./puppeteer.webworker.evaluatehandle.md) if [evaluate](./puppeteer.webworker.evaluate.md) cannot serialize the return value properly or you need a mutable [handle](./puppeteer.jshandle.md) to the return object.