mirror of
https://github.com/puppeteer/puppeteer
synced 2024-06-14 14:02:48 +00:00
63 lines
2.1 KiB
Markdown
63 lines
2.1 KiB
Markdown
<!-- Do not edit this file. It is automatically generated by API Documenter. -->
|
|
|
|
[Home](./index.md) > [puppeteer](./puppeteer.md) > [ExecutionContext](./puppeteer.executioncontext.md) > [evaluateHandle](./puppeteer.executioncontext.evaluatehandle.md)
|
|
|
|
## ExecutionContext.evaluateHandle() method
|
|
|
|
<b>Signature:</b>
|
|
|
|
```typescript
|
|
evaluateHandle(pageFunction: Function | string, ...args: unknown[]): Promise<JSHandle>;
|
|
```
|
|
|
|
## Parameters
|
|
|
|
| Parameter | Type | Description |
|
|
| --- | --- | --- |
|
|
| pageFunction | Function \| string | a function to be evaluated in the <code>executionContext</code> |
|
|
| args | unknown\[\] | argument to pass to the page function |
|
|
|
|
<b>Returns:</b>
|
|
|
|
Promise<[JSHandle](./puppeteer.jshandle.md)<!-- -->>
|
|
|
|
A promise that resolves to the return value of the given function as an in-page object (a [JSHandle](./puppeteer.jshandle.md)<!-- -->).
|
|
|
|
## Remarks
|
|
|
|
The only difference between `executionContext.evaluate` and `executionContext.evaluateHandle` is that `executionContext.evaluateHandle` returns an in-page object (a [JSHandle](./puppeteer.jshandle.md)<!-- -->). If the function passed to the `executionContext.evaluateHandle` returns a Promise, then `executionContext.evaluateHandle` would wait for the promise to resolve and return its value.
|
|
|
|
## Example 1
|
|
|
|
|
|
```js
|
|
const context = await page.mainFrame().executionContext();
|
|
const aHandle = await context.evaluateHandle(() => Promise.resolve(self));
|
|
aHandle; // Handle for the global object.
|
|
|
|
```
|
|
|
|
## Example 2
|
|
|
|
A string can also be passed in instead of a function.
|
|
|
|
```js
|
|
// Handle for the '3' * object.
|
|
const aHandle = await context.evaluateHandle('1 + 2');
|
|
|
|
```
|
|
|
|
## Example 3
|
|
|
|
JSHandle instances can be passed as arguments to the `executionContext.* evaluateHandle`<!-- -->:
|
|
|
|
```js
|
|
const aHandle = await context.evaluateHandle(() => document.body);
|
|
const resultHandle = await context.evaluateHandle(body => body.innerHTML, * aHandle);
|
|
console.log(await resultHandle.jsonValue()); // prints body's innerHTML
|
|
await aHandle.dispose();
|
|
await resultHandle.dispose();
|
|
|
|
```
|
|
|