Closing Form with WebBrowser control after window.close with C#

I recently had this problem. I have a Windows Form that hosts a WebBrowser control. The page in the WebBrowser control closes itself using window.close and when it does that the Windows Form freezes up.

Found a solution here posted by Jeff Sanders on his blog (thanks man!)

The sample code is provided in VB.NET Below is the same code rewritten in C#

public class ExtendedWebBrowser : WebBrowser
    {
        public const int WM_PARENTNOTIFY = 0x0210;
        public const int WM_DESTROY = 2;

        public delegate void ClosingEventHandler();
        public event ClosingEventHandler Closing;

        protected override void WndProc(ref Message m)
        {
            switch (m.Msg)
            {
                case WM_PARENTNOTIFY:
                    if (!this.DesignMode)
                    {
                        if (m.WParam.ToInt32() == WM_DESTROY)
                        {
                            if (this.Closing != null)
                            {
                                this.Closing();
                            }
                        }
                    }
                    base.DefWndProc(ref m);
                    break;

                default:
                    base.WndProc(ref m);
                    break;
            }
        }
    }