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SO上可能有500个这样的问题，并且有一百万个网站都提供信息花絮-但我就是看不到树木的树林。这似乎应该是令人尴尬的简单，但我就是无法让它发挥作用。

我有一个返回序列化 JSON 对象的 WCF Web 服务：

[OperationContract(Name = "PeopleData"), WebGet(BodyStyle = WebMessageBodyStyle.Bare, UriTemplate = "people/{subset}", ResponseFormat = WebMessageFormat.Json)]
PeopleObject GetPeople(string subset);

这可行 - 如果我从浏览器中点击该 URI，则会调用 GetPeople 并返回 JSON 序列化PeopleObject（此处为保护隐私而编辑的实际数据值）：

{"HashValue":"XXXXX","People":[{"EmailAddress":"XXXXX","EmployeeID":99999,"Gender":"X","JobTitle":"XXXXX","Office":"","PreferredName":"XXXXX","Surname":"XXXXX","WorkExtensionNumber":"XXXXX","WorkPhoneNumber":"XXXXX","Department":"XXXXX","DeskNumber":"XXXXX","EmploymentClassification":"XXXXX","InternationalExtensionNumber":"XXXXX","IsFirstAider":false,"Languages":[{"LanguageID":9,"LanguageSkillID":9},{"LanguageID":9,"LanguageSkillID":9}],"QualificationInitials":"XXXXX","QualificationTitle":"XXXXX","Secretaries":null,"WorkMobilePhoneNumber":"XXXXX"}],"RecordCount":"1","SizeBytes":"12345"}

在此示例中，PeopleObject有效负载仅包含Person集合中的一个对象，但可能包含许多对象（取决于/{subset}.

这是类层次结构PeopleObject- 它是一个顶级容器，包含一些关于有效负载的元数据，以及一个Person对象列表<>。这些对象又具有一堆简单的类型属性，以及两个进一步嵌套的 List<>Language和Secretary对象（可能填充也可能不填充）：

  [DataContract]
  public class PeopleObject
  {
    [DataMember]
    public string HashValue { get; set; }
    [DataMember]
    public List<Person> People { get; set; }
    [DataMember]
    public string RecordCount { get; set; }
    [DataMember]
    public string SizeBytes { get; set; }
  }

  [DataContract]
  public class Person
  {
    [DataMember]
    public string EmailAddress { get; set; }
    // <-- snip - lots of fields like this, no point listing them all here
    [DataMember]
    public bool IsFirstAider { get; set; }
    [DataMember]
    public List<Language> Languages { get; set; }
    [DataMember]
    public List<Secretary> Secretaries { get; set; }
  }

  [DataContract]
  public class Language
  {
    [DataMember]
    public int LanguageID { get; set; }
    [DataMember]
    public int LanguageSkillID { get; set; }
  }

  [DataContract]
  public class Secretary
  {
    [DataMember]
    public int EmployeeID { get; set; }
    [DataMember]
    public char FirstSurnameLetter { get; set; }
  }

到目前为止，一切都很好 - WCF 使用包含所有字段及其内容的 JSON 结构进行响应。现在在客户端应用程序中反序列化该结构（使用相同的类层次结构定义）：

  // I have a little helper-class to manage the WCF request and return a Stream
  using (Stream response = wcfHelper.GetRequestResponseStream(MY_WCF_URI))
  {
    // This is debug code to prove the response arrives as expected - it does
    //StreamReader sr = new StreamReader(response);
    //Console.WriteLine("\nResponse:\n{0}", sr.ReadToEnd());

    // Deserialise the response
    DataContractJsonSerializer dc = new DataContractJsonSerializer(typeof(PeopleObject));
    PeopleObject p = (PeopleObject)dc.ReadObject(response);

    // The object shows 1 record (in the example) but nothing in the List<>
    Console.WriteLine("\nDeserialized records: '{0}' [{1}]", p.RecordCount, p.People.Count);
  }

所以这正确地反序列化了容器对象，为我提供了记录计数、哈希值和有效负载大小（以字节为单位）。该对象也有一个 Person 对象的 List<>，但它是 null - JSON 响应中的内容没有通过创建和添加 Person 对象成功地重新水化 List<>。

我错过了什么？我的理解是，这种从 JSON 结构中对 C# 对象层次结构的再水化应该自动发生，所以要么不是这种情况（我需要编写一些代码来实现它），要么是这种情况，但我错过了一些明显的事情。

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1 回答 1

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我以前没有做过你正在做的事情，但从文档来看，我认为以下方法会起作用：

List<Type> types = new List<Type>();
types.Add(typeof(Person));
types.Add(typeof(Language));
types.Add(typeof(Secretary));

DataContractJsonSerializer dc = new DataContractJsonSerializer(typeof(PeopleObject), types);
PeopleObject p = (PeopleObject)dc.ReadObject(response);

您基本上需要告诉序列化器在序列化/反序列化对象时可能遇到的所有类型。

于 2013-06-20T13:00:35.630 回答