8370ec88ae
This change started as a small change to pull types from DefinitelyTyped over to
Puppeteer for the `evaluateHandle` function but instead ended up also fixing
what looks to be a long standing issue with our existing documentation.
`evaluateHandle` can in fact return an `ElementHandle` rather than a `JSHandle`.
Note that `ElementHandle` extends `JSHandle` so whilst the docs are technically
correct (all ElementHandles are JSHandles) it's confusing because JSHandles
don't have methods like `click` on them, but ElementHandles do.
if you return something that is an HTML element:
```
const button = page.evaluateHandle(() => document.querySelector('button'));
// this is an ElementHandle, not a JSHandle
```
Therefore I've updated the original docs and added a large explanation to the
TSDoc for `page.evaluateHandle`.
In TypeScript land we'll assume the function will return a `JSHandle` but you
can tell TS otherwise via the generic argument, which can only be `JSHandle`
(the default) or `ElementHandle`:
```
const button = page.evaluateHandle<ElementHandle>(() => document.querySelector('button'));
```
28 lines
862 B
Markdown
28 lines
862 B
Markdown
<!-- Do not edit this file. It is automatically generated by API Documenter. -->
|
|
|
|
[Home](./index.md) > [puppeteer](./puppeteer.md) > [Page](./puppeteer.page.md) > [waitForFunction](./puppeteer.page.waitforfunction.md)
|
|
|
|
## Page.waitForFunction() method
|
|
|
|
<b>Signature:</b>
|
|
|
|
```typescript
|
|
waitForFunction(pageFunction: Function | string, options?: {
|
|
timeout?: number;
|
|
polling?: string | number;
|
|
}, ...args: SerializableOrJSHandle[]): Promise<JSHandle>;
|
|
```
|
|
|
|
## Parameters
|
|
|
|
| Parameter | Type | Description |
|
|
| --- | --- | --- |
|
|
| pageFunction | Function \| string | |
|
|
| options | { timeout?: number; polling?: string \| number; } | |
|
|
| args | [SerializableOrJSHandle](./puppeteer.serializableorjshandle.md)<!-- -->\[\] | |
|
|
|
|
<b>Returns:</b>
|
|
|
|
Promise<[JSHandle](./puppeteer.jshandle.md)<!-- -->>
|
|
|