c# - 具有抽象(基)/具体(继承)类的 DataContractSerializer

Question

给定这段代码

public override void Serialize(BaseContentObject obj)
{
    string file = ObjectDataStoreFolder + obj.Slug + ".xml";
    if(obj.GetType() == typeof(Page))
    {
        DataContractSerializer dcs = new DataContractSerializer(typeof Page));
        XmlDictionaryWriter myWriter =
            XmlDictionaryWriter.CreateTextWriter(new FileStream(file, ileMode.CreateNew, FileAccess.Write),
                                             Encoding.UTF8);
        dcs.WriteObject(myWriter, obj);
        myWriter.Close();
    }
    else if(obj.GetType() == typeof(Image))
    {
        DataContractSerializer dcs = new DataContractSerializer(typeof Image));
        ...
        ...
    }
}

有没有办法做这样的事情

DataContractSerializer dcs = new DataContractSerializer(obj.GetType());
// this fails however, compiler error

并摆脱上面的那些 if() 语句？ DataContractSerializer 的构造函数需要 Type 或 Namespace，但它不适用于 obj.GetType()。

我的类层次结构如下:

BaseContentClass(抽象)

页面(具体，继承BaseContentClass)

Image(具体，继承BaseContentClass)

...

?

Answer 1

告诉序列化程序预期什么:

[KnownType(typeof(Page))]
[KnownType(typeof(Image))]
[DataContract]
public abstract class BaseContentObject { /* ... */ }

[DataContract]
public class Page : BaseContentObject { /* ... */ }

[DataContract]
public class Image : BaseContentObject { /* ... */ }

然后您可以使用 new DataContractSerializer(typeof(BaseContentObject )) 处理所有内容。