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CSharp · Console

/Program.cs

using System;
using System.Threading;
using System.Threading.Tasks;
using Nito.AsyncEx;

public static class Program
{
    static void Main()
    {
        AsyncContext.Run(async () =>
        {
            await DoSomethingAsync();
        });
    }

    static async Task DoSomethingAsync()
    {
        Console.WriteLine(SynchronizationContext.Current != null); // True
        await Task.Delay(3000);
        Console.WriteLine(SynchronizationContext.Current != null); // True
    }
}