自定义一个可以被序列化的泛型Dictionary集合

Dictionary是一个键值类型的集合。它有点像数组，但Dictionary的键可以是任何类型，内部使用Hash Table存储键和值。本篇自定义一个类型安全的泛型Dictionary<TKey, TValue>,并且可以被序列化。

为了使自定义的泛型Dictionary<TKey, TValue>可以被序列化成xml，需要实现泛型IXmlSerializable接口。

    public class MySerializableDictionary<TKey, TValue> : Dictionary<TKey, TValue>, IXmlSerializable

    {

        public System.Xml.Schema.XmlSchema GetSchema()

        {

            return null;

        }


        public void ReadXml(System.Xml.XmlReader reader)

        {

            //键的xml序列化器

            XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));


            //值的xml序列化器

            XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));


            //判断xml中当前节点是否为null

            bool wasEmpty = reader.IsEmptyElement;


            reader.Read();


            if (wasEmpty)

            {

                return;

            }


            while (reader.NodeType != System.Xml.XmlNodeType.EndElement)

            {

               //先读键

                reader.ReadStartElement("item");

                reader.ReadStartElement("key");


                //反序列化成键的类型

                TKey key = (TKey) keySerializer.Deserialize(reader);

                reader.ReadEndElement();


                //再读值

                reader.ReadStartElement("value");

                TValue value = (TValue)valueSerializer.Deserialize(reader);

                reader.ReadEndElement();


                this.Add(key, value);

                reader.ReadEndElement();


                //读下一个节点

                reader.MoveToContent();

            }


            reader.ReadEndElement();

        }


        public void WriteXml(System.Xml.XmlWriter writer)

        {

            //键的xml序列化器

            XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));


            //值的xml序列化器

            XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));


            foreach (TKey key in this.Keys)

            {

                writer.WriteStartElement("item");

                writer.WriteStartElement("key");

                keySerializer.Serialize(writer, key);

                writer.WriteEndElement();


                writer.WriteStartElement("value");

                TValue value = this[key];

                valueSerializer.Serialize(writer, value);

                writer.WriteEndElement();

                writer.WriteEndElement();

            }

        }

    }

客户端使用XmlWriter把Dictionary<TKey, TValue>这个泛型集合写进xml中。

    class Program

    {

        static void Main(string[] args)

        {

            MySerializableDictionary<int, string> mySerializableDictionary = new MySerializableDictionary<int, string>();

            mySerializableDictionary.Add(1,"darren");

            mySerializableDictionary.Add(2, "jack");


            using (XmlWriter writer = XmlWriter.Create("infos.xml"))

            {

                writer.WriteStartDocument();

                writer.WriteStartElement("infos");


                foreach (var item in mySerializableDictionary)

                {

                    mySerializableDictionary.WriteXml(writer);

                }


                writer.WriteEndElement();

                writer.WriteEndDocument();

            }

            Console.WriteLine("写入xml成功");

            Console.ReadKey();

        }

    }

在Debug文件夹中可找到生成的infos.xml文件。