2.0 KiB
2.0 KiB
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ExecutionContext.evaluateHandle |
ExecutionContext.evaluateHandle() method
Signature:
class ExecutionContext {evaluateHandle<Params extends unknown[], Func extends EvaluateFunc<Params> = EvaluateFunc<Params>>(pageFunction: Func | string, ...args: Params): Promise<HandleFor<Awaited<ReturnType<Func>>>>;}
Parameters
Parameter | Type | Description |
---|---|---|
pageFunction | Func | string | a function to be evaluated in the executionContext |
args | Params | argument to pass to the page function |
Returns:
Promise<HandleFor<Awaited<ReturnType<Func>>>>
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();