The source of the registration helper

/// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
/// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
/// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
/// PARTICULAR PURPOSE.

/// Copyright (c) Siemens Product Lifecycle Management Software Inc. All rights reserved.

using Microsoft.Win32;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace SolidEdge.AddIn.Common
{
    /// <summary>
    /// Helper class for ComRegisterFunction and ComUnregisterFunction attributes.
    /// </summary>
    public static class RegistrationHelper
    {
        public static void Register(Type t)
        {
            var addinInfo = (AddInInfoAttribute)AddInInfoAttribute.GetCustomAttribute(t, typeof(AddInInfoAttribute));
            var environments = (AddInEnvironmentCategoryAttribute[])AddInEnvironmentCategoryAttribute.GetCustomAttributes(t, typeof(AddInEnvironmentCategoryAttribute));

            if (addinInfo == null) throw new System.Exception("Missing AddInInfoAttribute.");
            if ((environments == null) || (environments.Length == 0))
            {
                throw new System.Exception("Missing AddInEnvironmentCategoryAttribute.");
            }

            string subkey = String.Format(@"CLSID\{0}", t.GUID.ToString("B"));
            using (RegistryKey baseKey = Registry.ClassesRoot.CreateSubKey(subkey))
            {
                subkey = String.Format(@"Implemented Categories\{0}", CategoryIDs.CATID_SolidEdgeAddIn);
                using (RegistryKey implementedCategoriesKey = baseKey.CreateSubKey(subkey))
                {
                }

                foreach (var environment in environments)
                {
                    subkey = String.Format(@"Environment Categories\{0}", environment.Guid.ToString("B"));
                    using (RegistryKey environmentCategoryKey = baseKey.CreateSubKey(subkey))
                    {
                    }
                }

                using (RegistryKey summaryKey = baseKey.CreateSubKey("Summary"))
                {
                    summaryKey.SetValue("409", addinInfo.Summary);
                }

                baseKey.SetValue("AutoConnect", addinInfo.AutoConnect ? 1 : 0);
                baseKey.SetValue("409", addinInfo.Title);
            }
        }

        public static void Unregister(Type t)
        {
            string subkey = String.Format(@"CLSID\{0}", t.GUID.ToString("B"));
            Registry.ClassesRoot.DeleteSubKeyTree(subkey, false);
        }
    }
}