puppeteer/new-docs/puppeteer.page.__eval.md

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<!-- Do not edit this file. It is automatically generated by API Documenter. -->
[Home](./index.md) &gt; [puppeteer](./puppeteer.md) &gt; [Page](./puppeteer.page.md) &gt; [$$eval](./puppeteer.page.__eval.md)
## Page.$$eval() method
This method runs `Array.from(document.querySelectorAll(selector))` within the page and passes the result as the first argument to the `pageFunction`<!-- -->.
<b>Signature:</b>
```typescript
$$eval<ReturnType>(selector: string, pageFunction: (elements: Element[], ...args: unknown[]) => ReturnType | Promise<ReturnType>, ...args: SerializableOrJSHandle[]): Promise<WrapElementHandle<ReturnType>>;
```
## Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| selector | string | the [selector](https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Selectors) to query for |
| pageFunction | (elements: Element\[\], ...args: unknown\[\]) =&gt; ReturnType \| Promise&lt;ReturnType&gt; | the function to be evaluated in the page context. Will be passed the result of <code>Array.from(document.querySelectorAll(selector))</code> as its first argument. |
| args | [SerializableOrJSHandle](./puppeteer.serializableorjshandle.md)<!-- -->\[\] | any additional arguments to pass through to <code>pageFunction</code>. |
<b>Returns:</b>
Promise&lt;[WrapElementHandle](./puppeteer.wrapelementhandle.md)<!-- -->&lt;ReturnType&gt;&gt;
The result of calling `pageFunction`<!-- -->. If it returns an element it is wrapped in an [ElementHandle](./puppeteer.elementhandle.md)<!-- -->, else the raw value itself is returned.
## Remarks
If `pageFunction` returns a promise `$$eval` will wait for the promise to resolve and then return its value.
## Example 1
```
// get the amount of divs on the page
const divCount = await page.$$eval('div', divs => divs.length);
// get the text content of all the `.options` elements:
const options = await page.$$eval('div > span.options', options => {
return options.map(option => option.textContent)
});
```
If you are using TypeScript, you may have to provide an explicit type to the first argument of the `pageFunction`<!-- -->. By default it is typed as `Element[]`<!-- -->, but you may need to provide a more specific sub-type:
## Example 2
```
// if you don't provide HTMLInputElement here, TS will error
// as `value` is not on `Element`
await page.$$eval('input', (elements: HTMLInputElement[]) => {
return elements.map(e => e.value);
});
```
The compiler should be able to infer the return type from the `pageFunction` you provide. If it is unable to, you can use the generic type to tell the compiler what return type you expect from `$$eval`<!-- -->:
## Example 3
```
// The compiler can infer the return type in this case, but if it can't
// or if you want to be more explicit, provide it as the generic type.
const allInputValues = await page.$$eval<string[]>(
'input', (elements: HTMLInputElement[]) => elements.map(e => e.textContent)
);
```