using System;

using System.Collections.Generic;

using System.Threading.Tasks;

using System.Linq;

​

public class Program

{

    public async static Task Main()

    {

​

        List<string> names = ["Alice", "Bob", "Charlie"];

​

        var upperCaseNamesList = await names

            .ToAsyncEnumerable()

            .SelectAwait(async name =>

                         {

                             // simulate an asynchronous operation

                             await Task.Delay(100); 

                             return name.ToUpper();

                         })

            .ToListAsync();

​

        Console.WriteLine(string.Join(",", upperCaseNamesList));

    }

}