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66 lines
2.1 KiB
Markdown
66 lines
2.1 KiB
Markdown
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---
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sidebar_label: ExecutionContext.evaluateHandle
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---
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# ExecutionContext.evaluateHandle() method
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**Signature:**
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```typescript
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class ExecutionContext {
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evaluateHandle<
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Params extends unknown[],
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Func extends EvaluateFunc<Params> = EvaluateFunc<Params>
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>(
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pageFunction: Func | string,
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...args: Params
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): Promise<HandleFor<Awaited<ReturnType<Func>>>>;
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}
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```
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## Parameters
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| Parameter | Type | Description |
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| ------------ | -------------- | --------------------------------------------------------------- |
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| pageFunction | Func \| string | a function to be evaluated in the <code>executionContext</code> |
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| args | Params | argument to pass to the page function |
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**Returns:**
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Promise<[HandleFor](./puppeteer.handlefor.md)<Awaited<ReturnType<Func>>>>
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A promise that resolves to the return value of the given function as an in-page object (a [JSHandle](./puppeteer.jshandle.md)).
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## Remarks
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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.
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## Example 1
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```ts
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const context = await page.mainFrame().executionContext();
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const aHandle = await context.evaluateHandle(() => Promise.resolve(self));
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aHandle; // Handle for the global object.
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```
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## Example 2
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A string can also be passed in instead of a function.
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```ts
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// Handle for the '3' * object.
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const aHandle = await context.evaluateHandle('1 + 2');
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```
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## Example 3
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JSHandle instances can be passed as arguments to the `executionContext.* evaluateHandle`:
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```ts
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const aHandle = await context.evaluateHandle(() => document.body);
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const resultHandle = await context.evaluateHandle(body => body.innerHTML, * aHandle);
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console.log(await resultHandle.jsonValue()); // prints body's innerHTML
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await aHandle.dispose();
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await resultHandle.dispose();
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```
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