C# SerializableDictionary

SerializableDictionary.cs

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

/// <summary>
/// Base on https://weblogs.asp.net/pwelter34/444961
/// </summary>
/// <typeparam name="TKey"></typeparam>
/// <typeparam name="TValue"></typeparam>
[XmlRoot("dictionary")]
public class SerializableDictionary<TKey, TValue> : Dictionary<TKey, TValue>, IXmlSerializable
{
    // XmlSerializer.Deserialize() will create a new Object, and then call ReadXml()
    // So cannot use instance field, use class field.

    public static string itemTag = "item";
    public static string keyTag = "key";
    public static string valueTag = "value";

    public XmlSchema GetSchema()
    {
        return null;
    }

    public void ReadXml(XmlReader reader)
    {
        if (reader.IsEmptyElement)
            return;

        var keySerializer = new XmlSerializer(typeof(TKey));
        var valueSerializer = new XmlSerializer(typeof(TValue));

        reader.ReadStartElement();

        // IsStartElement() will call MoveToContent()
        // reader.MoveToContent();
        while (reader.IsStartElement(itemTag))
        {
            reader.ReadStartElement(itemTag);

            reader.ReadStartElement(keyTag);
            TKey key = (TKey)keySerializer.Deserialize(reader);
            reader.ReadEndElement();

            reader.ReadStartElement(valueTag);
            TValue value = (TValue)valueSerializer.Deserialize(reader);
            reader.ReadEndElement();

            reader.ReadEndElement();
            this.Add(key, value);

            // IsStartElement() will call MoveToContent()
            // reader.MoveToContent();
        }
        reader.ReadEndElement();
    }

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

        foreach (var kvp in this)
        {
            writer.WriteStartElement(itemTag);

            writer.WriteStartElement(keyTag);
            keySerializer.Serialize(writer, kvp.Key);
            writer.WriteEndElement();

            writer.WriteStartElement(valueTag);
            valueSerializer.Serialize(writer, kvp.Value);
            writer.WriteEndElement();

            writer.WriteEndElement();
        }
    }
}

SerializableDictionaryDemo.cs

using System;
using System.IO;
using System.Xml.Serialization;

//[XmlRoot("AnimalDictionary")]
public class SDict : SerializableDictionary<string, string>
{
}

namespace Test
{
    public class Program
    {

        static void Main(string[] args)
        {
            var dict = new SDict();
            //SDict.itemTag = "AnimalCount";
            //SDict.keyTag = "Type";
            //SDict.valueTag = "Count";
            dict.Add("Cat", "1");
            dict.Add("Dog", "2");

            foreach (var kvp in dict)
                Console.WriteLine(kvp);

            XmlSerializer serializer = new XmlSerializer(typeof(SDict));

            using (var writer = new StreamWriter("dict.xml"))
            {
                serializer.Serialize(writer, dict);
            }

            Console.WriteLine("\nXML File:");
            Console.WriteLine(File.ReadAllText("dict.xml"));

            using (var reader = new StreamReader("dict.xml"))
            {
                dict = serializer.Deserialize(reader) as SDict;
            }

            Console.WriteLine("\nAfter Deserialize");

            foreach (var kvp in dict)
                Console.WriteLine(kvp);

            Console.ReadLine();
        }
    }
}

Thanks so much for this, dropped in and just worked perfectly for my need 🎉