puppeteer/website/versioned_docs/version-9.1.1/puppeteer.page.evaluatehandle.md
2021-08-10 11:09:48 +01:00

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[Home](./index.md) &gt; [puppeteer](./puppeteer.md) &gt; [Page](./puppeteer.page.md) &gt; [evaluateHandle](./puppeteer.page.evaluatehandle.md)
## Page.evaluateHandle() method
<b>Signature:</b>
```typescript
evaluateHandle<HandlerType extends JSHandle = JSHandle>(pageFunction: EvaluateHandleFn, ...args: SerializableOrJSHandle[]): Promise<HandlerType>;
```
## Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| pageFunction | [EvaluateHandleFn](./puppeteer.evaluatehandlefn.md) | a function that is run within the page |
| args | [SerializableOrJSHandle](./puppeteer.serializableorjshandle.md)\[\] | arguments to be passed to the pageFunction |
<b>Returns:</b>
Promise&lt;HandlerType&gt;
## Remarks
The only difference between [page.evaluate](./puppeteer.page.evaluate.md) and `page.evaluateHandle` is that `evaluateHandle` will return the value wrapped in an in-page object.
If the function passed to `page.evaluteHandle` returns a Promise, the function will wait for the promise to resolve and return its value.
You can pass a string instead of a function (although functions are recommended as they are easier to debug and use with TypeScript):
## Example 1
```
const aHandle = await page.evaluateHandle('document')
```
## Example 2
[JSHandle](./puppeteer.jshandle.md) instances can be passed as arguments to the `pageFunction`:
```
const aHandle = await page.evaluateHandle(() => document.body);
const resultHandle = await page.evaluateHandle(body => body.innerHTML, aHandle);
console.log(await resultHandle.jsonValue());
await resultHandle.dispose();
```
Most of the time this function returns a [JSHandle](./puppeteer.jshandle.md), but if `pageFunction` returns a reference to an element, you instead get an [ElementHandle](./puppeteer.elementhandle.md) back:
## Example 3
```
const button = await page.evaluateHandle(() => document.querySelector('button'));
// can call `click` because `button` is an `ElementHandle`
await button.click();
```
The TypeScript definitions assume that `evaluateHandle` returns a `JSHandle`, but if you know it's going to return an `ElementHandle`, pass it as the generic argument:
```
const button = await page.evaluateHandle<ElementHandle>(...);
```