C# 8.0 introduced the concept of asynchronous streams using IAsyncEnumerable<T>. This feature allows you to handle data sequences where each element is generated asynchronously and efficiently. It's beneficial when dealing with I/O-bound operations, such as reading from a network stream or a database.
In the below example, the GenerateNumbersAsync method is an IAsyncEnumerable<int> that asynchronously produces numbers. The await foreach loop asynchronously consumes these numbers as they become available.
Asynchronous streams are incredibly valuable for scenarios where you want to avoid blocking the calling thread while waiting for asynchronous data to arrive. This can include scenarios like streaming data from a web API or reading a large file asynchronously.
Use asynchronous streams carefully, as they can add complexity to your code. They are most beneficial when dealing with scenarios where asynchronous data production is a natural fit.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
public class Program
{
public static async Task Main()
{
await foreach (var number in GenerateNumbersAsync())
{
Console.WriteLine(number);
}
}
public static async IAsyncEnumerable<int> GenerateNumbersAsync()
{
for (int i = 1; i <= 5; i++)
{
// Simulate an asynchronous operation
await Task.Delay(100);
yield return i;
}
}
}