.net - 如何将派生类序列化为其基类

Question

我有一个派生类，它只向基类添加方法。如何序列化派生类以使其与基类的序列化相匹配？
即派生类的序列化 xml 应如下所示:

<BaseClass>
  ...
</BaseClass>

例如
以下将抛出 InvalidOperationException

The type DerivedClass was not expected. Use the XmlInclude or SoapInclude attribute to specify types that are not known statically.

Class BaseClass {}

Class DerivedClass : BaseClass {}

DerivedClass derived = new DerivedClass();

StreamWriter stream = new StreamWriter("output file path");
XmlSerializer serializer = new XmlSerializer(GetType(BaseClass));
serializer(stream, derived);

Answer 1

您必须将 GetType(DerivedClass) 传递给序列化器构造函数，它必须与您序列化的对象的类型相匹配。您可以使用 <XmlRoot>属性重命名为根元素。此示例代码按预期工作:

using System;
using System.Xml.Serialization;
using System.IO;

class Program {
  static void Main(string[] args) {
    var obj = new DerivedClass();
    obj.Prop = 42;
    var xs = new XmlSerializer(typeof(DerivedClass));
    var sw = new StringWriter();
    xs.Serialize(sw, obj);
    Console.WriteLine(sw.ToString());

    var sr = new StringReader(sw.ToString());
    var obj2 = (BaseClass)xs.Deserialize(sr);
    Console.ReadLine();
  }
}

public class BaseClass {
  public int Prop { get; set; }
}
[XmlRoot("BaseClass")]
public class DerivedClass : BaseClass { }