From: Thomas Sondergaard <thomas@...>
Date: 2003-09-28T19:31:42+09:00
Subject: Re: RubyDotNet and Drag and Drop

Apparently there is a need to set the COM ApartmentState to STA

Adding this in the first line of the ruby Init_dotnet function makes it go
away:

System::Threading::Thread::CurrentThread->ApartmentState =
System::Threading::ApartmentState::STA;

Cheers,

Thomas

"Wayne Vucenic" <wvucenic@netgate.net> wrote in message
news:182202853037.20030927220828@netgate.net...
> I just heard about RubyDotNet, and it looks really great!
>
> I did encounter a problem while trying to use drag and drop.  (RubyDotNet
> r4, Ruby 1.8, .NET 1.1, Windows XP).  Here's a stripped down piece of
> code that demonstrates the problem:
>
>      require 'dotnet'
>
>      loadLibrary 'System.Windows.Forms'
>
>      form = Form.new
>      form.topMost = true
>      form.text = 'Drag and Drop Test'
>      form.AllowDrop = true;
>
>      Application.Run form
>
> When I run this I get a "Microsoft .NET Framework" dialog saying "An
> unhandled exception has occurred in your application...DragDrop
> registration failed" with the following details:
>
> ************** Exception Text **************
> System.InvalidOperationException: DragDrop registration failed. --->
> System.Threading.ThreadStateException: The current thread must set to
> Single Thread Apartment (STA) mode before OLE calls can be made.
> Ensure that your Main function has STAThreadAttribute marked on it.
> at System.Windows.Forms.Control.SetAcceptDrops(Boolean accept)
> --- End of inner exception stack trace ---
> at System.Windows.Forms.Control.SetAcceptDrops(Boolean accept)
> at System.Windows.Forms.Control.OnHandleCreated(EventArgs e)
> at System.Windows.Forms.Form.OnHandleCreated(EventArgs e)
> at System.Windows.Forms.Control.WmCreate(Message& m)
> at System.Windows.Forms.Control.WndProc(Message& m)
> at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
> at System.Windows.Forms.ContainerControl.WndProc(Message& m)
> at System.Windows.Forms.Form.WmCreate(Message& m)
> at System.Windows.Forms.Form.WndProc(Message& m)
> at System.Windows.Forms.ControlNativeWindow.OnMessage(Message& m)
> at System.Windows.Forms.ControlNativeWindow.WndProc(Message& m)
> at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg,
> IntPtr wparam, IntPtr lparam)
>
> Thanks!!!
>
> Wayne
> No Bugs Software
> "Ruby and C++ Contract Programming in Silicon Valley"
>
>