XmlSerializer 构造函数 (Type, String) 将指定类型的对象序列化为 XML 文档，也可以将 XML 文档反序列化为指定类型的对象

 private void SerializeObject(string filename) {
        XmlSerializer serializer = new XmlSerializer
            (typeof(OrderedItem), "http://www.cpandl.com");

        // Create an instance of the class to be serialized.
        OrderedItem i = new OrderedItem();

        // Insert code to set property values.

        // Writing the document requires a TextWriter.
        TextWriter writer = new StreamWriter(filename);
        // Serialize the object, and close the TextWriter
        serializer.Serialize(writer, i);
        writer.Close();
    }

    private void DeserializeObject(string filename) {
        XmlSerializer serializer = new XmlSerializer
            (typeof(OrderedItem), "http://www.cpandl.com");
        // A FileStream is needed to read the XML document.
        FileStream fs = new FileStream(filename, FileMode.Open);

        // Declare an object variable of the type to be deserialized.
        OrderedItem i;

        // Deserialize the object.
        i = (OrderedItem) serializer.Deserialize(fs);

        // Insert code to use the properties and methods of the object.
    }