CodeTV.MainForm.UpdateChannelNumberRecursedTree C# (CSharp) Method

        private void UpdateChannelNumberRecursedTree(ChannelFolder channelFolder)
        {
            foreach (Channel channel in channelFolder.ChannelList)
            {
                if (channel is ChannelTV)
                {
                    short channelNumber = (channel as ChannelTV).ChannelNumber;
                    channelNumberMax = Math.Max(channelNumberMax, channelNumber);
                    if (channelNumber >= 0)
                    {
                        if (this.channelByChannelNumber.ContainsKey(channelNumber))
                            this.cloneChannelNumber.Add(channel);
                        else
                            this.channelByChannelNumber[channelNumber] = channel;
                    }
                }
                else if (channel is ChannelFolder)
                    UpdateChannelNumberRecursedTree(channel as ChannelFolder);
            }
        }