c# - 未知属性 xsi :type in XmlSerializer

Question

我正在学习 XML 序列化并遇到一个问题，我有两个类(class)

[System.Xml.Serialization.XmlInclude(typeof(SubClass))]
public class BaseClass
{

}

public class SubClass : BaseClass
{
}

我正在尝试将一个 SubClass 对象序列化为 XML 文件，我使用的是代码

XmlSerializer xs = new XmlSerializer(typeof(Base));
xs.Serialize(fs, SubClassObject);

我注意到序列化成功了，但是 XML 文件有点像

<?xml version="1.0"?>
<BaseClass xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xsi:type="SubClass">
...
</Employee>

如果我用

XmlSerializer xs = new XmlSerializer(typeof(Base));
SubClassObject = xs.Deserialize(fs) as SubClass;

我注意到它会提示 xsi:type is unknown attribute(我注册了一个事件)，尽管 XML 中嵌入的所有信息都已成功解析并且 SubClassObject 中的成员已正确恢复。

有人知道为什么在解析 xsi:type 时出错以及我做错了什么吗？

谢谢

Answer 1

这是我写的程序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml.Serialization;
using System.IO;

namespace XmlIncludeExample
{
    [XmlInclude(typeof(DerivedClass))]
    public class BaseClass
    {
        public string ClassName = "Base Class";
    }

    public class DerivedClass : BaseClass
    {
        public string InheritedName = "Derived Class";
    }

    class Program
    {
        static void Main(string[] args)
        {
            string fileName = "Test.xml";
            string fileFullPath = Path.Combine(Path.GetTempPath(), fileName);

            try
            {
                DerivedClass dc = new DerivedClass();

                using (FileStream fs = new FileStream(fileFullPath, FileMode.CreateNew))
                {
                    XmlSerializer xs = new XmlSerializer(typeof(BaseClass));
                    xs.Serialize(fs, dc);
                }

                using (FileStream fs = new FileStream(fileFullPath, FileMode.Open))
                {
                    XmlSerializer xs = new XmlSerializer(typeof(BaseClass));
                    DerivedClass dc2 = xs.Deserialize(fs) as DerivedClass;
                }
            }
            finally
            {
                if (File.Exists(fileFullPath))
                {
                    File.Delete(fileFullPath);
                }
            }
        }
    }
}

这产生了以下 xml

<?xml version="1.0" ?> 
- <BaseClass xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xsi:type="DerivedClass">
  <ClassName>Base Class</ClassName> 
  <InheritedName>Derived Class</InheritedName> 
  </BaseClass>

成功了