ZeroInstall.Publish.Capture.SnapshotDiff.GetAutoPlay C# (CSharp) Method

        private static Capability GetAutoPlay([NotNull] string handler, [NotNull] RegistryKey hive, [NotNull, ItemNotNull] IEnumerable<ComparableTuple<string>> autoPlayAssocs, [NotNull] CommandMapper commandMapper)
        {
            #region Sanity checks
            if (handler == null) throw new ArgumentNullException(nameof(handler));
            if (hive == null) throw new ArgumentNullException(nameof(hive));
            if (autoPlayAssocs == null) throw new ArgumentNullException(nameof(autoPlayAssocs));
            if (commandMapper == null) throw new ArgumentNullException(nameof(commandMapper));
            #endregion

            using (var handlerKey = hive.OpenSubKey(DesktopIntegration.Windows.AutoPlay.RegKeyHandlers + @"\" + handler))
            {
                if (handlerKey == null) return null;

                string progID = handlerKey.GetValue(DesktopIntegration.Windows.AutoPlay.RegValueProgID, "").ToString();
                string verbName = handlerKey.GetValue(DesktopIntegration.Windows.AutoPlay.RegValueVerb, "").ToString();

                using (var progIDKey = Registry.ClassesRoot.OpenSubKey(progID))
                {
                    if (progIDKey == null) throw new IOException(progID + " key not found");
                    var autoPlay = new AutoPlay
                    {
                        ID = handler,
                        Provider = handlerKey.GetValue(DesktopIntegration.Windows.AutoPlay.RegValueProvider, "").ToString(),
                        Descriptions = {handlerKey.GetValue(DesktopIntegration.Windows.AutoPlay.RegValueDescription, "").ToString()},
                        Verb = GetVerb(progIDKey, commandMapper, verbName)
                    };

                    autoPlay.Events.AddRange(
                        from autoPlayAssoc in autoPlayAssocs
                        where autoPlayAssoc.Value == handler
                        select new AutoPlayEvent {Name = autoPlayAssoc.Key});

                    return autoPlay;
                }
            }
        }
    }