Exposing Windows Forms Controls as ActiveX controls

using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Windows.Forms;

// Add in these	using clauses for this example
using System.Runtime.InteropServices;
using System.Text;
using System.Reflection;
using Microsoft.Win32;

namespace Prisoner
{
	///	<summary>
	///	Summary	description	for	UserControl1.
	///	</summary>
	[ProgId("Prisoner.PrisonerControl")]
	[ClassInterface(ClassInterfaceType.AutoDual)]
	public class PrisonerControl : System.Windows.Forms.UserControl
	{
		private	System.Windows.Forms.PictureBox	pictureBox1;
		private	System.Windows.Forms.Label label1;
		///	<summary>
		///	Required designer variable.
		///	</summary>
		private	System.ComponentModel.Container	components = null;

		public PrisonerControl()
		{
			// This	call is	required by	the	Windows.Forms Form Designer.
			InitializeComponent();

			// TODO: Add any initialization	after the InitForm call

		}

		///	<summary>
		///	Clean up any resources being used.
		///	</summary>
		protected override void	Dispose( bool disposing	)
		{
			if(	disposing )
			{
				if(	components != null )
					components.Dispose();
			}
			base.Dispose( disposing	);
		}

		#region	Component Designer generated code
		///	<summary>
		///	Required method	for	Designer support - do not modify 
		///	the	contents of	this method	with the code editor.
		///	</summary>
		private	void InitializeComponent()
		{
			System.Resources.ResourceManager resources = new System.Resources.ResourceManager(typeof(PrisonerControl));
			this.pictureBox1 = new System.Windows.Forms.PictureBox();
			this.label1	= new System.Windows.Forms.Label();
			this.SuspendLayout();
			// 
			// pictureBox1
			// 
			this.pictureBox1.Image = ((System.Drawing.Bitmap)(resources.GetObject("pictureBox1.Image")));
			this.pictureBox1.Location =	new	System.Drawing.Point(8,	8);
			this.pictureBox1.Name =	"pictureBox1";
			this.pictureBox1.Size =	new	System.Drawing.Size(112, 120);
			this.pictureBox1.TabIndex =	0;
			this.pictureBox1.TabStop = false;
			// 
			// label1
			// 
			this.label1.Location = new System.Drawing.Point(8, 136);
			this.label1.Name = "label1";
			this.label1.Size = new System.Drawing.Size(328,	40);
			this.label1.TabIndex = 1;
			this.label1.Text = "I am not a number, I am	a free man.";
			// 
			// PrisonerControl
			// 
			this.Controls.AddRange(new System.Windows.Forms.Control[] {
																		  this.label1,
																		  this.pictureBox1});
			this.Name =	"PrisonerControl";
			this.Size =	new	System.Drawing.Size(344, 184);
			this.ResumeLayout(false);

		}
		#endregion

		public void	Question ( )
		{
			MessageBox.Show	( "Who is number one?" ) ;
		}

		///	<summary>
		///	Register the class as a	control	and	set	it's CodeBase entry
		///	</summary>
		///	<param name="key">The registry key of the control</param>
		[ComRegisterFunction()]
		public static void RegisterClass ( string key )
		{
			// Strip off HKEY_CLASSES_ROOT\ from the passed key as I don't need it
			StringBuilder	sb = new StringBuilder ( key ) ;
			sb.Replace(@"HKEY_CLASSES_ROOT\","") ;

			// Open the CLSID\{guid} key for write access
			RegistryKey k	= Registry.ClassesRoot.OpenSubKey(sb.ToString(),true);

			// And create	the	'Control' key -	this allows	it to show up in
			// the ActiveX control container
			RegistryKey ctrl = k.CreateSubKey	( "Control"	) ;
			ctrl.Close ( ) ;

			// Next create the CodeBase entry	- needed if	not	string named and GACced.
			RegistryKey inprocServer32 = k.OpenSubKey	( "InprocServer32" , true )	;
			inprocServer32.SetValue (	"CodeBase" , Assembly.GetExecutingAssembly().CodeBase )	;
			inprocServer32.Close ( ) ;

			// Finally close the main	key
			k.Close (	) ;
		}

		///	<summary>
		///	Called to unregister the control
		///	</summary>
		///	<param name="key">Tke registry key</param>
		[ComUnregisterFunction()]
		public static void UnregisterClass ( string	key	)
		{
			StringBuilder	sb = new StringBuilder ( key ) ;
			sb.Replace(@"HKEY_CLASSES_ROOT\","") ;

			// Open	HKCR\CLSID\{guid} for write	access
			RegistryKey	k =	Registry.ClassesRoot.OpenSubKey(sb.ToString(),true);

			// Delete the 'Control'	key, but don't throw an	exception if it	does not exist
			k.DeleteSubKey ( "Control" , false ) ;

			// Next	open up	InprocServer32
			RegistryKey	inprocServer32 = k.OpenSubKey (	"InprocServer32" , true	) ;

			// And delete the CodeBase key,	again not throwing if missing
			k.DeleteSubKey ( "CodeBase"	, false	) ;

			// Finally close the main key
			k.Close	( )	;
		}

	}
}