docs/api/puppeteer.page.evaluatehandle.md
class Page {
evaluateHandle<
Params extends unknown[],
Func extends EvaluateFunc<Params> = EvaluateFunc<Params>,
>(
pageFunction: Func | string,
...args: Params
): Promise<HandleFor<Awaited<ReturnType<Func>>>>;
}
Parameter
</th><th>Type
</th><th>Description
</th></tr></thead> <tbody><tr><td>pageFunction
</td><td>Func | string
</td><td>a function that is run within the page
</td></tr> <tr><td>args
</td><td>Params
</td><td>arguments to be passed to the pageFunction
</td></tr> </tbody></table>Returns:
Promise<HandleFor<Awaited<ReturnType<Func>>>>
The only difference between page.evaluate and page.evaluateHandle is that evaluateHandle will return the value wrapped in an in-page object.
If the function passed to page.evaluateHandle 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):
const aHandle = await page.evaluateHandle('document');
JSHandle 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, but if pageFunction returns a reference to an element, you instead get an ElementHandle back:
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>(...);