6474edb9ba
This pulls in the types (based on the DefinitelyTyped repo) for `page.$eval` (and the `$eval` method on other classes). The `$eval` method is quite hard to type due to the way we wrap and unwrap ElementHandles that are passed to / returned from the `pageFunction` that users provide. Longer term we can improve the types by providing type overloads as DefinitelyTyped does but I've deferred that for now (see the `TODO` in the code for more details).
1.5 KiB
1.5 KiB
Home > puppeteer > ElementHandle > $eval
ElementHandle.$eval() method
This method runs document.querySelector
within the element and passes it as the first argument to pageFunction
. If there's no element matching selector
, the method throws an error.
If pageFunction
returns a Promise, then frame.$eval
would wait for the promise to resolve and return its value.
Signature:
$eval<ReturnType>(selector: string, pageFunction: (element: Element, ...args: unknown[]) => ReturnType | Promise<ReturnType>, ...args: SerializableOrJSHandle[]): Promise<WrapElementHandle<ReturnType>>;
Parameters
Parameter | Type | Description |
---|---|---|
selector | string | |
pageFunction | (element: Element, ...args: unknown[]) => ReturnType | Promise<ReturnType> | |
args | SerializableOrJSHandle[] |
Returns:
Promise<WrapElementHandle<ReturnType>>
Example
const tweetHandle = await page.$('.tweet');
expect(await tweetHandle.$eval('.like', node => node.innerText)).toBe('100');
expect(await tweetHandle.$eval('.retweets', node => node.innerText)).toBe('10');