Async / Await可在Windows Form应用程序中使用，但不应

Question

Based on MSDN article following code shouldn't work in Windows Forms application and I'm pretty much certain, that it didn't work in past, but recently I've discovered, that in .NET framework 4.7.02558 it works.

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    public void Test()
    {
        Console.WriteLine("One");

        var d = DelayAsync();

        Console.WriteLine("Three");

        d.Wait();
        Console.WriteLine("Five");
    }

    private async Task DelayAsync()
    {
        Console.WriteLine("Two");

        await Task.Delay(1000);
        Console.WriteLine("Four");
    }

    private void Button1_Click(object sender, EventArgs e)
    {
        Test();
    }
}

Did I miss some a release log, or is something wrong (I mean right from user's perspective)?

Edit: An application should freeze after returning from awaited code because in Windows Forms is used CurrentContextSheduller.

Answer 1

Testing on 4.7.1 I get the following results:

One
Two
Three

Four , and Five never get displayed. It seems to be "not-working as intended" for me, as execution of await Task.Delay(1000); is blocking.

Answer 2

Discovered. The problem was caused by ReSharper Build & Run. For some reason, the build wasn't done and switching from ReSharper Build to Visual Studio build program behaves "correctly". Latest build was done with .ConfigureAway(false) , so that's a root cause of why it worked and shouldn't.