c# - XML 序列化具有抽象基类的可序列化对象的通用列表

Question

任何关于如何使用抽象基类序列化通用对象列表的好示例。 XML Serialize generic list of serializable objects 中列出了具有非抽象基类的示例.我的基类类似于 Microsoft.Build.Utilities.Task

Answer 1

另一种方法是使用 XmlElementAttribute 将已知类型列表移动到通用列表本身...

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

public abstract class Animal
{
    public int Weight { get; set; }    
}

public class Cat : Animal
{
    public int FurLength { get; set; }    
}

public class Fish : Animal
{
    public int ScalesCount { get; set; }    
}

public class AnimalFarm
{
    [XmlElement(typeof(Cat))]
    [XmlElement(typeof(Fish))]
    public List<Animal> Animals { get; set; }

    public AnimalFarm()
    {
        Animals = new List<Animal>();
    }
}

public class Program
{
    public static void Main()
    {
        AnimalFarm animalFarm = new AnimalFarm();
        animalFarm.Animals.Add(new Cat() { Weight = 4000, FurLength = 3 });
        animalFarm.Animals.Add(new Fish() { Weight = 200, ScalesCount = 99 });
        XmlSerializer serializer = new XmlSerializer(typeof(AnimalFarm));
        serializer.Serialize(Console.Out, animalFarm);
    }
}

...这也将导致更好看的 XML 输出(没有丑陋的 xsi:type 属性)...

<?xml version="1.0" encoding="ibm850"?>
<AnimalFarm xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <Cat>
    <Weight>4000</Weight>
    <FurLength>3</FurLength>
  </Cat>
  <Fish>
    <Weight>200</Weight>
    <ScalesCount>99</ScalesCount>
  </Fish>
</AnimalFarm>