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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.


static forEachAsync<TEntry>(array: TEntry[], callback: (entry: TEntry, arrayIndex: number) => Promise<void>, options?: IAsyncParallelismOptions | undefined): Promise<void>;


Parameter Type Description
array 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 options for customizing the control flow




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.