VBA 是否支持从 C# 类导入的 Task.Wait()？

Question

I wrote a C# class which connects to Dropbox and lets you upload, download, delete and generate link files.

It's working with a Windows Forms but I have to access it from VBA (Microsoft Access). The problem comes when it goes to task.Wait(). I've ""debugged" this throwing Exceptions and after that, doesn't go through.

public DropBox()
{
    //Empty constructor because VBA doesn't support constructors with args
}

public void Connect(string tokenUser)
{
    try
    {
        dropbox = new DropboxClient(tokenUser);
        var taskInicio = Task.Run(async () => await dropbox.Users.GetCurrentAccountAsync());
        //throw new Exception("Arriving?");   //ARRIVES
        taskInicio.Wait();
        throw new Exception("Arriving?");    //Throws "one or more errors"
    }
    catch (AggregateException ex)
    when (ex.InnerException is BadInputException
          || ex.InnerException is AuthException)
    {
        throw new Exception("Incorrect Token or without access", ex.InnerException);
    }
}

On VBA

Option Compare Database

Private Sub btActivar_Click()
    Call test
End Sub

Public Function test()

    Dim objDrop As CloudFiles.DropBox
    Set objDrop = New CloudFiles.DropBox

    MsgBox (objDrop.HolaMundo)
    objDrop.Connect("TokenLongChicken")
    'objDrop.DeleteFile("https://www.dropbox.com/s...?dl=0")


End Function

The "One or more errors produced" sounds like it comes from the "mscorlib" or so...

Any ideas? This is getting quite messy :/

Thanks.

Answer 1

VBA does have Application.Wait , I think you can give it a try. I have a code to wait for an IE connection which you can use as example:

Do While IE.Busy ' Need to wait until the page has loaded
  Application.Wait (Now + TimeValue("00:00:01")) ' Wait one second
Loop

Tell me if it helps you.

Answer 2

I was having headaches thinking that it could be something related with the Tasks, asyncs, awaits... and it was something related with the Newtonsoft json library.

I updated the library through the NuGet to the 9.0 version and everything worked fine on Windows Forms, but looks like something is wrong when I use it through the .TLB because when I escaped the exception I got at some point in my deletion method, it said the Newtonsoft Json 7.0.0.0 library was missing (it was at the same directory anyway).

I finally removed that Newtonsoft Json version I was using and the Dropbox API, downloaded box again but I declined applying any updates. I couldn't even try to apply a downgrade or so.

Good ending, but I don't really get why did it search for the 7.0.0.0 when I was using the 9.x on my Windows Form project, which works and exported the .DLL and the .TLB.

Thanks to everybody.

EDIT: And yes, I guess this answers the question: VBA supports Task.Wait (at least coming from a C# .dll import)