c# - 序列化中的 System.OverflowException

Question

我有一些用于解析网络响应的类:

[DataContract]
public abstract class GYResponse 
{
    [DataMember(Name = "code")]
    public int Code { get; set; }
    [DataMember(Name = "message")]
    public string Message { get; set; }
}

[DataContract]
public class ResponseGetUser : GYResponse
{
    [DataMember(Name = "result")]
    public GYUser Result { get; set; }
}

[DataContract]
public class ResponseGetVenue : GYResponse
{
    [DataMember(Name = "result")]
    public GYVenue Result { get; set; }
}

我使用DataContractJsonSerializer:

GYResponse response_obj = request.Creater.CreateResponseObj(); 
//CreateResponseObj() return ResponseGetUser, ResponseGetVenue etc

using (MemoryStream stream = new MemoryStream(Encoding.Unicode.GetBytes(gyResponse)))
{
    DataContractJsonSerializer serializer = new DataContractJsonSerializer(response_obj.GetType());                   
    response_obj = (GYResponse)serializer.ReadObject(stream);       
}

我有 "System.OverflowException" 行:

response_obj = (GYResponse)serializer.ReadObject(stream); 

/checked 编译器选项已关闭。而 ReadObject 不能抛出这个异常。

但如果我重写这些类，它就可以工作了:

[DataContract]
public abstract class GYResponse 
{

}

[DataContract]
public class ResponseGetUser : GYResponse
{
    [DataMember(Name = "result")]
    public GYUser Result { get; set; }
    [DataMember(Name = "code")]
    public int Code { get; set; }
    [DataMember(Name = "message")]
    public string Message { get; set; }
}

[DataContract]
public class ResponseGetVenue : GYResponse
{
    [DataMember(Name = "result")]
    public GYVenue Result { get; set; }
    [DataMember(Name = "code")]
    public int Code { get; set; }
    [DataMember(Name = "message")]
    public string Message { get; set; }
}

我知道这是一个模糊的问题，但不明白可能是什么问题。什么时候可以抛出这个异常？

更新异常信息:

留言:

 There was an error deserializing the object of type GotYou.RequesterService.ResponseGetInfo. Value was either too large or too small for an Int32.

内部异常:

at System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info)
   at System.String.System.IConvertible.ToInt32(IFormatProvider provider)
   at System.Convert.ChangeType(Object value, Type conversionType, IFormatProvider provider)
   at System.Runtime.Serialization.Json.DataContractJsonSerializer.ConvertObjectToPrimitiveDataContract(DataContract contract, Object value, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.DataContractJsonSerializer.ConvertObjectToDataContract(DataContract contract, Object value, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.ObjectToDataContractConverter.ReadClassDataContractMembers(DataContractJsonSerializer serializer, ClassDataContract dataContract, Dictionary`2 deserialzedValue, Object newInstance, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.ObjectToDataContractConverter.ReadClassDataContractMembers(DataContractJsonSerializer serializer, ClassDataContract dataContract, Dictionary`2 deserialzedValue, Object newInstance, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.ObjectToDataContractConverter.ConvertDictionaryToClassDataContract(DataContractJsonSerializer serializer, ClassDataContract dataContract, Dictionary`2 deserialzedValue, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.DataContractJsonSerializer.ConvertObjectToDataContract(DataContract contract, Object value, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.ObjectToDataContractConverter.ReadClassDataContractMembers(DataContractJsonSerializer serializer, ClassDataContract dataContract, Dictionary`2 deserialzedValue, Object newInstance, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.ObjectToDataContractConverter.ConvertDictionaryToClassDataContract(DataContractJsonSerializer serializer, ClassDataContract dataContract, Dictionary`2 deserialzedValue, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.DataContractJsonSerializer.ConvertObjectToDataContract(DataContract contract, Object value, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.ObjectToDataContractConverter.ReadClassDataContractMembers(DataContractJsonSerializer serializer, ClassDataContract dataContract, Dictionary`2 deserialzedValue, Object newInstance, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.ObjectToDataContractConverter.ConvertDictionaryToClassDataContract(DataContractJsonSerializer serializer, ClassDataContract dataContract, Dictionary`2 deserialzedValue, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.DataContractJsonSerializer.ConvertObjectToDataContract(DataContract contract, Object value, XmlObjectSerializerReadContextComplexJson context)
   at System.Runtime.Serialization.Json.DataContractJsonSerializer.ReadObject(Stream stream)

轨迹跟踪:

 at System.Runtime.Serialization.Json.DataContractJsonSerializer.ReadObject(Stream stream)
   at GotYou.RequesterService.PostRequester.getResponseCallback(IAsyncResult asynchronousResult)

JSON 响应:

{
    "code": 0,
    "message": "",
    "result": {
        "uid": "51da997decaa3ca351000000",
        "url": "",
        "nickname": "Smileman",
        "avatar": "\/img\/profile_pics\/users\/51da997decaa3ca351000000\/cache\/avatar48x48.jpg?lastUpdate=1381215566",
        "age": {
            "number": "22",
            "suffix": "года",
            "birthday": "1991-04-17"
        },
        "sex": 1,
        "aboutself": "",
        "premium": true,
        "isFriend": 3,
        "online": {
            "lastVisit": "7 минут назад",
            "status": true
        },
        "features": {
            "car": false,
            "house": false,
            "cash": false,
            "group": true
        },
        "location": {
            "longitude": 36.570838832,
            "latitude": 50.571069472,
            "timestamp": 1381319677
        },
        "bonuses": 8515,
        "address": "",
        "city": {
            "code": "3100000100000",
            "title": ""
        },
        "cover": "\/img\/profile_pics\/users\/51da997decaa3ca351000000\/cache\/hero480x290.jpg?lastUpdate=1381215566",
        "distance": 63.671441859659,
        "paidServices": {
            "vip": true,
            "theming": true,
            "invisible": false,
            "incognito": false,
            "closed": true
        },
        "regdate": "19.08.2013",
        "purpose": {
            "id": "500fa718ecaa3c6e3b000002",
            "title": ""
        }
    }
}

Answer 1

您数据中的这个数字:3100000100000 对于 Int32 来说太大了拿着它。 Int32 的最大正值是 2147483647。您可以考虑使用 Int64 (UInt32 也太小了，因为它的范围结束于 4294967295)。

但是，code 字段通常被解释为字符串，所以也许 string 数据类型是更好的选择，例如:

[DataMember(Name = "code")]
public string Code { get; set; }