Wierd threading issues with WebBrowser control

[Warren]

I don't understand what's going on in the following program. I believe it
should simply create a form with a browser in it and navigate that browser to
Google. However, the constructor for the WebBrowser is throwing a
ThreadStateExce ption saying ActiveX control
'8856f961-340a-11d0-a96b-00c04fd705a2' cannot be instantiated because the
current thread is not in a single-threaded apartment. Any ideas what's going
on?

using System;
using System.Collecti ons.Generic;
using System.Text;
using System.Windows. Forms;

namespace Project1
{
class Class1
{
public static void Main()
{
Application.Run (new Form1());
}
}

class Form1 : Form
{
public Form1()
{
WebBrowser b = new WebBrowser();
b.Navigate("www .google.com");
this.Controls.A dd(b);
}
}
}

Thanks
-Warren

[Jon Skeet [C# MVP]]

Re: Wierd threading issues with WebBrowser control

Warren <Warren@discuss ions.microsoft. com> wrote:[color=blue]
> I don't understand what's going on in the following program. I believe it
> should simply create a form with a browser in it and navigate that browser to
> Google. However, the constructor for the WebBrowser is throwing a
> ThreadStateExce ption saying ActiveX control
> '8856f961-340a-11d0-a96b-00c04fd705a2' cannot be instantiated because the
> current thread is not in a single-threaded apartment. Any ideas what's going
> on?[/color]

It means exactly what it says - you're not running in an STA. If you
put the [STAThread] attribute on your Main method, you should be fine.

--
Jon Skeet - <skeet@pobox.co m>

http://www.pobox.com/~skeet

If replying to the group, please do not mail me too

[Warren]

Re: Wierd threading issues with WebBrowser control

"Jon Skeet [C# MVP]" wrote:
[color=blue]
> Warren <Warren@discuss ions.microsoft. com> wrote:[color=green]
> > I don't understand what's going on in the following program. I believe it
> > should simply create a form with a browser in it and navigate that browser to
> > Google. However, the constructor for the WebBrowser is throwing a
> > ThreadStateExce ption saying ActiveX control
> > '8856f961-340a-11d0-a96b-00c04fd705a2' cannot be instantiated because the
> > current thread is not in a single-threaded apartment. Any ideas what's going
> > on?[/color]
>
> It means exactly what it says - you're not running in an STA. If you
> put the [STAThread] attribute on your Main method, you should be fine.
>
> --
> Jon Skeet - <skeet@pobox.co m>
> http://www.pobox.com/~skeet
> If replying to the group, please do not mail me too
>[/color]

Thanks a bunch! I'd seen that on Windows Forms Designer generated code, but
never had any idea what it did.