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Async.forEachAsync() method
This API is provided as a preview for developers and may change based on feedback that we receive. Do not use this API in a production environment.
Given an input array and a callback function, invoke the callback to start a promise for each element in the array.
Signature:
static forEachAsync<TEntry>(iterable: Iterable<TEntry> | AsyncIterable<TEntry>, callback: (entry: TEntry, arrayIndex: number) => Promise<void>, options?: IAsyncParallelismOptions | undefined): Promise<void>;
Parameters
| Parameter | Type | Description |
|---|---|---|
| iterable | Iterable<TEntry> | AsyncIterable<TEntry> | the array of inputs for the callback function |
| callback | (entry: TEntry, arrayIndex: number) => Promise<void> | a function that starts an asynchronous promise for an element from the array |
| options | IAsyncParallelismOptions | undefined | (Optional) options for customizing the control flow |
Returns:
Promise<void>
Remarks
This API is similar to the system Array#forEach, except that the loop is asynchronous, and the maximum number of concurrent promises can be throttled using IAsyncParallelismOptions.concurrency.
If callback throws a synchronous exception, or if it returns a promise that rejects, then the loop stops immediately. Any remaining array items will be skipped, and overall operation will reject with the first error that was encountered.