Random use of a custom config with nested keys.

MessageDisplayConfig.cs

namespace Core.Configuration
{
  using System;
	using System.Configuration;

	public class MessageConfigurationSection : ConfigurationSection
	{
		[ConfigurationProperty("messages", IsDefaultCollection = false)]
		[ConfigurationCollection(typeof (MessageCollection), AddItemName = "add", ClearItemsName = "clear", RemoveItemName = "remove")]
		public MessageCollection Messages
		{
			get { return base["messages"] as MessageCollection; }
		}
	}

	public class MessageCollection : ConfigurationElementCollection
	{
		public MessageCollection()
		{
			var url = (MessageElement) CreateNewElement();
			Add(url);
		}

		public override ConfigurationElementCollectionType CollectionType
		{
			get { return ConfigurationElementCollectionType.AddRemoveClearMap; }
		}

		public MessageElement this[int index]
		{
			get { return (MessageElement) BaseGet(index); }
			set
			{
				if (BaseGet(index) != null)
				{
					BaseRemoveAt(index);
				}
				BaseAdd(index, value);
			}
		}

		public new MessageElement this[string name]
		{
			get { return (MessageElement) BaseGet(name); }
		}

		protected override ConfigurationElement CreateNewElement()
		{
			return new MessageElement();
		}

		protected override Object GetElementKey(ConfigurationElement element)
		{
			return ((MessageElement) element).Name;
		}

		public int IndexOf(MessageElement url)
		{
			return BaseIndexOf(url);
		}

		public void Add(MessageElement url)
		{
			BaseAdd(url);
		}

		protected override void BaseAdd(ConfigurationElement element)
		{
			BaseAdd(element, false);
		}

		public void Remove(MessageElement url)
		{
			if (BaseIndexOf(url) >= 0)
				BaseRemove(url.Name);
		}

		public void RemoveAt(int index)
		{
			BaseRemoveAt(index);
		}

		public void Remove(string name)
		{
			BaseRemove(name);
		}

		public void Clear()
		{
			BaseClear();
		}
	}

	public class MessageElement : ConfigurationElement
	{
		[ConfigurationProperty("name", IsRequired = true, IsKey = true)]
		public string Name
		{
			get { return base["name"] as string; }
			set { base["name"] = value; }
		}

		[ConfigurationProperty("title", IsRequired = true, IsKey = false)]
		public string Title
		{
			get { return base["title"] as string; }
			set { base["title"] = value; }
		}

		[ConfigurationProperty("copy", IsRequired = true, IsKey = false)]
		public string Copy
		{
			get { return base["copy"] as string; }
			set { base["copy"] = value; }
		}

		[ConfigurationProperty("startDate", IsRequired = false, IsKey = false)]
		public DateTime StartDate
		{
			get { return Convert.ToDateTime(base["startDate"]); }
			set { base["startDate"] = value; }
		}

		[ConfigurationProperty("endDate", IsRequired = false, IsKey = false)]
		public DateTime EndDate
		{
			get { return Convert.ToDateTime(base["endDate"]); }
			set { base["endDate"] = value; }
		}
	}
}