A SerializableDictionary in C#

If you create a static Dictionary in code, every time you need to change the dictionary, you have change code, recompile, and redeploy. Wouldn’t it be nice if you didn’t have to change code. What if you could create your dictionary in an Xml file and deserialize it. You can now make the change outside of code.

using System.Collections.Generic;
using System.Xml.Serialization;

namespace Rhyous.EasyXml
{
    [XmlRoot("Dictionary")]
    public class SerializableDictionary<TKey, TValue>
        : Dictionary<TKey, TValue>, IXmlSerializable
    {
        public string KeyName = "key";
        public string ValueName = "value";

        #region constructors
        public SerializableDictionary()
        {
        }

        public SerializableDictionary(IEqualityComparer<TKey> comparer)
            : base(comparer)
        {
        }
        #endregion



        #region IXmlSerializable Members
        public System.Xml.Schema.XmlSchema GetSchema()
        {
            return null;
        }

        public void ReadXml(System.Xml.XmlReader reader)
        {
            var keySerializer = new XmlSerializer(typeof(TKey), null, null, new XmlRootAttribute(KeyName), null);
            var valueSerializer = new XmlSerializer(typeof(TValue), null, null, new XmlRootAttribute(ValueName), null);

            var wasEmpty = reader.IsEmptyElement;
            reader.Read();

            if (wasEmpty)
                return;

            while (reader.NodeType != System.Xml.XmlNodeType.EndElement)
            {
                var key = (TKey)keySerializer.Deserialize(reader);
                var value = (TValue)valueSerializer.Deserialize(reader);
                Add(key, value);
                reader.MoveToContent();
            }
            reader.ReadEndElement();
        }

        public void WriteXml(System.Xml.XmlWriter writer)
        {
            var keySerializer = new XmlSerializer(typeof(TKey));
            var valueSerializer = new XmlSerializer(typeof(TValue));

            foreach (TKey key in Keys)
            {
                keySerializer.Serialize(writer, key);
                valueSerializer.Serialize(writer, this[key]);
            }
        }
        #endregion
    }
}

One Comment

  1. Nick R. says:

    I was using some older similar code but this appears to do the same. The problem I'm having right now is that this code doesn't address the situations where the dictionary value is a list of objects. For instance:

    SerializableDictionary<string, List> _dictCLSIDs = new SerializableDictionary<string, List> { };

    The code is unable to serialize this dictionary. I'll need to unserialize it as well.

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