Question

我能够成功地将包含Employee和Manager对象混合的列表序列化为JSON。

但是，当我尝试将JSON反序列化回List时，我正在丢失子类中的所有字段数据，当我尝试转换为任何一个子类时，我得到一个空值。如何在不丢失Employee和Manager子类字段中的数据的情况下反序列化这些用户的列表？

[DataContract]
public class User {
  [DataMember]
  public string FirstName { get; set; }
  [DataMember]
  public string LastName { get; set; }
}

[DataContract]
public class Employee : User {
  [DataMember]
  public string JobTitle { get; set; }
}  

[DataContract]
public class Manager : User {
  [DataMember]
  public string Department { get; set; }
}

编辑 - 这是我的荒漠化代码：

// abridged
public void Client() {
  var jsonContent = jsonResponse.Content;
  var entityList = Deserialize<IEnumerable<T>>(new JsonMediaTypeFormatter(), jsonContent);
}

protected T Deserialize<T>(MediaTypeFormatter formatter, string str) where T : class {
    // Write the serialized string to a memory stream.
    Stream stream = new MemoryStream();
    StreamWriter writer = new StreamWriter(stream);
    writer.Write(str);
    writer.Flush();
    stream.Position = 0;
    // Deserialize to an object of type T
    return formatter.ReadFromStreamAsync(typeof(T), stream, null, null).Result as T;
}

Answer 1

您可以使用DataContractJsonSerializer将一组已知类型作为序列化器构造函数参数传递来实现。

我创建了一个简单的测试代码来演示：

var list = new List<User>() {
    new User { FirstName = "user1", LastName = "user1" },
    new Employee { FirstName = "employee1", LastName = "employee1", JobTitle = "employee1" },
    new Manager() { FirstName = "manager1", LastName = "manager1", Department = "manager1"}
};

var serializer = new DataContractJsonSerializer(typeof(List<User>), new [] { typeof(Employee), typeof(Manager) });

string json;
using (var stream = new MemoryStream())
{
    serializer.WriteObject(stream, list);
    stream.Position = 0;
    using(var reader = new StreamReader(stream))
    {
        json = reader.ReadToEnd();
    }
}

List<User> list2;

using(var stream = new MemoryStream())
{
    using(var writer = new StreamWriter(stream))
    {
        writer.Write(json);
        writer.Flush();
        stream.Position = 0;
        list2 = (List<User>)serializer.ReadObject(stream);
    }
}

C＃将不同接口实现的JSON列表反序列化为列表而不丢失数据

1 个答案: