await IAsyncEnumerable<T> where is it used?

August 22, 2022

It says here:

Starting with C# 8.0, IAsyncEnumerable, for an async method that
returns an async stream.

Question. In addition to the specified example with foreach, is it possible to use more the await with IAsyncEnumerable somehow, or is it designed specially for foreach? I think yes, but not sure. Perhaps there are other purposes.

await foreach (var number in GetNumbersAsync())
{
    Console.WriteLine(number);
}

async IAsyncEnumerable<int> GetNumbersAsync()
{
    for (int i = 0; i < 10; i++)
    {
        await Task.Delay(100);
        yield return i;
    }
}

>Solution :

As Jeremy Lakeman said in the comments, you can use it however you want. There is nothing magic about it. Simply call .GetAsyncEnumerator() on your IAsyncEnumerable and then you can use that as you would a regular enumerator, but with async support.

Example:

IAsyncEnumerator<int> e = GetNumbersAsync().GetAsyncEnumerator();
try
{
  while (await e.MoveNextAsync())
    Console.Write(e.Current + " ");
}
finally {
  if (e != null)
    await e.DisposeAsync();
}

The sample was taken from here: https://docs.microsoft.com/en-us/archive/msdn-magazine/2019/november/csharp-iterating-with-async-enumerables-in-csharp-8