XmlSerializer
无法处理接口,因为它不知道反序列化时要创建哪些类型。为了解决这个问题,您需要通过实现IXmlSerializable
接口自己处理序列化的那部分。这允许您记录类型,以便您可以重新创建(反序列化)它。
下面的ListOfIAnimal
类显示了我如何继承和扩展通用列表List<IAnimal>
以实现所需的接口。我压缩了你的旧类,为每个类添加了一个额外的非接口字段,这样我就可以看到具体类正在正确地序列化和反序列化。
与您的代码相比,我只是使用新类型ListOfIAnimal
代替List<IAnimal>
,其他更改只是一些重构。
它的完整代码,只需将它复制到它自己的.cs文件中,调用第一个函数来单步执行它。
using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Xml;
using System.Xml.Serialization;
namespace Serialiser
{
static class SerialiseInterface
{
public static void SerialiseAnimals()
{
String finalXml;
// Serialize
{
var animals = new ListOfIAnimal{
new Dog() { Age = 5, Teeth = 30 },
new Cat() { Age = 6, Paws = 4 }
};
var xmlSerializer = new XmlSerializer(animals.GetType());
var stringBuilder = new StringBuilder();
var xmlTextWriter = XmlTextWriter.Create(stringBuilder, new XmlWriterSettings { NewLineChars = "\r\n", Indent = true });
xmlSerializer.Serialize(xmlTextWriter, animals);
finalXml = stringBuilder.ToString();
}
// Deserialise
{
var xmlSerializer = new XmlSerializer(typeof(ListOfIAnimal));
var xmlReader = XmlReader.Create(new StringReader(finalXml));
ListOfIAnimal animals = (ListOfIAnimal)xmlSerializer.Deserialize(xmlReader);
}
}
}
public class ListOfIAnimal : List<IAnimal>, IXmlSerializable
{
public ListOfIAnimal() : base() { }
#region IXmlSerializable
public System.Xml.Schema.XmlSchema GetSchema() { return null; }
public void ReadXml(XmlReader reader)
{
reader.ReadStartElement("ListOfIAnimal");
while (reader.IsStartElement("IAnimal"))
{
Type type = Type.GetType(reader.GetAttribute("AssemblyQualifiedName"));
XmlSerializer serial = new XmlSerializer(type);
reader.ReadStartElement("IAnimal");
this.Add((IAnimal)serial.Deserialize(reader));
reader.ReadEndElement(); //IAnimal
}
reader.ReadEndElement(); //ListOfIAnimal
}
public void WriteXml(XmlWriter writer)
{
foreach (IAnimal animal in this)
{
writer.WriteStartElement("IAnimal");
writer.WriteAttributeString("AssemblyQualifiedName", animal.GetType().AssemblyQualifiedName);
XmlSerializer xmlSerializer = new XmlSerializer(animal.GetType());
xmlSerializer.Serialize(writer, animal);
writer.WriteEndElement();
}
}
#endregion
}
public interface IAnimal { int Age { get; set; } }
public class Dog : IAnimal { public int Age { get; set;} public int Teeth { get; set;} }
public class Cat : IAnimal { public int Age { get; set;} public int Paws { get; set;} }
}
我曾考虑将反序列化作为练习留给读者,但如果没有它,代码将非常有用。