2.1 KiB
2.1 KiB
Home > puppeteer > ExecutionContext > evaluateHandle
ExecutionContext.evaluateHandle() method
Signature:
evaluateHandle<HandleType extends JSHandle | ElementHandle = JSHandle>(pageFunction: EvaluateHandleFn, ...args: SerializableOrJSHandle[]): Promise<HandleType>;
Parameters
| Parameter | Type | Description |
|---|---|---|
| pageFunction | EvaluateHandleFn | a function to be evaluated in the executionContext |
| args | SerializableOrJSHandle[] | argument to pass to the page function |
Returns:
Promise<HandleType>
A promise that resolves to the return value of the given function as an in-page object (a JSHandle).
Remarks
The only difference between executionContext.evaluate and executionContext.evaluateHandle is that executionContext.evaluateHandle returns an in-page object (a JSHandle). 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
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.
// 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:
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();