使用嵌套列表反序列化json对象

时间:2011-12-16 20:30:20

标签: c# asp.net json

我有一个包含嵌套列表的对象和一个使用自定义转换器和.net的javascript序列化器从json反序列化它的方法。像这样:

public class MyObject{
      int TheID { get; set; }
      public List<MyNestedObject1> ListOfMyNestedObject1 { get; set; }  
      public List<MyNestedObject2> ListOfMyNestedObject2 { get; set; }

      public MyObject ObjectFromJson(string TheObjectInJson) {

        JavaScriptSerializer TheSerializer = new JavaScriptSerializer();
        TheSerializer.RegisterConverters(new JavaScriptConverter[] {
            new MyObjectConvert()
        });
        TheSerializer.RegisterConverters(new JavaScriptConverter[] {
            new MyNestedObject1Convert()
        });
        TheSerializer.RegisterConverters(new JavaScriptConverter[] {
            new MyNestedObject2Convert()
        });
        //if I comment out the registrations of the converters, it works
        //but I need the converters of the nested objects to kick in
        return TheSerializer.Deserialize<MyObject>(TheObjectInJson);       
    }
}

嵌套对象的json转换器如下所示:

public class MyNestedObject1Convert : JavaScriptConverter {

  public override IEnumerable<Type> SupportedTypes {
      get { return new Type[] { typeof(MyNestedObject1Convert) };
  }
  public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer) 
  { //deserialization logic
    return MyNestedObject1;}
}

MyObject的转换器如下所示:

public class MyObjectConvert : JavaScriptConverter {

  public override IEnumerable<Type> SupportedTypes { get { return new Type[] { typeof(MyObjectConvert) }; }  

  public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer) {

    int TheID;
    MyObject TheObject = new MyObject();

    int.TryParse(serializer.ConvertToType<string>(dictionary["TheID"]), out TheID))
    TheObject.ID = TheID;

    return TheObject;
    }
}

现在,接收json字符串并看起来返回c#对象的调用函数如下所示:

MyObject AMyObject = new MyObject();
MyObject TheMyObject = new MyObject();

TheMyObject = AMyObject.ObjectFromJson(JsonString);

当我运行此代码时,返回的对象包含TheID,但嵌套对象为null。我在对象方法中注册转换器,但我猜这不是这样做的方法。如果我删除了转换器的注册,则对象包含嵌套对象,但转换器不会启动。

我需要改变什么?注意:我不打算使用其他库,只是为了使本机反序列化器工作。

感谢您的建议。

1 个答案:

答案 0 :(得分:1)

好的,所以我让它上班了。如果您希望反序列化嵌套列表,可以按照以下方式进行操作。

首先,不要在MyObject ObjectFromJson方法中注册转换器。

其次,在MyObject的自定义转换器中,您可以对嵌套列表进行反序列化。像这样:

 public class MyObjectConvert : JavaScriptConverter {

  public override IEnumerable<Type> SupportedTypes { get { return new Type[] { typeof(MyObjectConvert) }; }  

  public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer) {

    int TheID;
    MyObject TheObject = new MyObject();

    int.TryParse(serializer.ConvertToType<string>(dictionary["TheID"]), out TheID))
    TheObject.ID = TheID;

    if (dictionary.ContainsKey("ListOfMyNestedObject1"))
    {
      serializer.RegisterConverters(new JavaScriptConverter[] { new MyNestedObject1Convert() });
      var TheList = serializer.ConvertToType<List<MyNestedObject1>>(dictionary["ListOfMyNestedObject1"]);
      TheObject.ListOfMyNestedObject1 = TheList
    }

    return TheObject;
    }
}

瞧:json使用.net的javascriptserializer使用自定义javascript转换器对嵌套列表进行反序列化。