问题
I'm trying to use JSON.Net to deserialize a JSON object into a C# object.
The object I want to create is MonthlyPerformance which contains a list of Type, which contains a list of Categories, which in turn contains a list of Funds. They are defined as:
public class MonthlyPerformance
{
public List<Type> Types { get; set; }
}
public class Type
{
public int Id { get; set; }
public string CountryId { get; set; }
public string Name { get; set; }
public List<Category> Categories { get; set; }
public Type()
{
}
}
public class Category
{
public int Id { get; set; }
public string CountryId { get; set; }
public string Name { get; set; }
public List<ConfigurationFund> Funds { get; set; }
public Category()
{
}
}
public class Fund
{
public int Id { get; set; }
public string CountryId { get; set; }
public string Name { get; set; }
public Fund()
{
}
}
I thought the following would do it, but it's not. It's just creating an instance of the Type object with everything null:
var file = File.ReadAllText(filePath);
var types = JsonConvert.DeserializeObject<Type>(file);
This is the JSON that I'm using:
{
"MonthlyPerformance": {
"Type": [
{
"id": "65",
"countryId": "IE",
"name": "Irish Domestic Funds (Gross)",
"Category": [
{
"id": "25003334",
"countryId": "IE",
"name": "UK Equity",
"ConfigurationFund": [
{
"id": "25000301",
"countryId": "IE",
"name": "Aviva Irl UK Equity Fund"
},
{
"id": "25000349",
"countryId": "IE",
"name": "New Ireland UK Equity 9"
}
]
},
{
"id": "25003339",
"countryId": "IE",
"name": "Irish Equity",
"Fund": [
{
"id": "25000279",
"countryId": "IE",
"name": "Friends First Irish Equity G"
},
{
"id": "25000305",
"countryId": "IE",
"name": "Irish Life Celticscope 2 G"
}
]
}
]
},
{
"id": "80",
"countryId": "IE",
"name": "Irish Individual Pensions",
"Category": [
{
"id": "25003347",
"countryId": "IE",
"name": "Asia Pacific Ex-Japan Equity",
"Fund": [
{
"id": "25001789",
"countryId": "IE",
"name": "Aviva Irl Pacific Basin Eq"
},
{
"id": "25002260",
"countryId": "IE",
"name": "Ir Life Pacific Eq Indexed P"
}
]
},
{
"id": "25003365",
"countryId": "IE",
"name": "Flexible Equity",
"Fund": [
{
"id": "25003238",
"countryId": "IE",
"name": "Friends First Protected Equity Plus Fund S2"
},
{
"id": "25003267",
"countryId": "IE",
"name": "Friends First Protected Equity Plus Bond G"
}
]
}
]
}
]
}
}
What do I need to do to get this to work?
edited to include MonthlyPerformance
回答1:
I believe the problem is in your Json string.
"Type": [ ... ]
Should be
"Types": [ ... ]
Types is the name of property that should be deserialized, you mistakenly put Type the class name instead.
The same goes for Categories property in the Type class.
Also I simply removed "MonthlyPerformance" root from the Json string and it worked like a charm. With Json.NET of course.
Here is a snippets of the modified Json with appropriate property names (notice, Types, Categories, Funds and the absence of MonthlyPerformance root)
{
"Types": [
{
"id": "65",
"countryId": "IE",
"name": "Irish Domestic Funds (Gross)",
"Categories": [
{
"id": "25003334",
"countryId": "IE",
"name": "UK Equity",
"Funds": [
{
"id": "25000301",
"countryId": "IE",
"name": "Aviva Irl UK Equity Fund"
},
{
"id": "25000349",
"countryId": "IE",
"name": "New Ireland UK Equity 9"
}
]
}
回答2:
the above code that you have for your classes looks correct on first glance.
i've been successful with deserializing JSON with the following class(JavaScriptSerializer). used as follows
using System.Web.Script.Serialization;
JavaScriptSerializer js = new JavaScriptSerializer();
string file = File.ReadAllText(filePath);
MonthyPerformance json = js.Deserialize<MonthlyPerformance>(file);
oh, and add [Serializable] to your class attributes for each class
[Serializable]
class whatever{}
回答3:
Would you think to use dynamic object instead of deserializing to an object? (without declaring MonthlyPerformance, Type, Category, Fund)
Facebook C# SDK get user language/region
Google Maps v3 geocoding server-side
Usage:
dynamic jobj = JsonUtils.JsonObject.GetDynamicJsonObject(JsonString);
foreach (var item in jobj.MonthlyPerformance.Type)
{
Console.WriteLine(item.name);
foreach (var category in item.Category)
{
Console.WriteLine("\t" + category.name);
if (category.ConfigurationFund != null)
{
foreach (var fund in category.ConfigurationFund)
{
Console.WriteLine("\t\t" + fund.name);
}
}
}
}
Helper class needed is here
回答4:
Your property names do not match that of your JSON. I would expect the serialization to fail.
Given the JSON you posted I would expect your c# classes to look like this. I'm not familiar with JSON.net but I would assume they have a property decorator that would allow you to specify the name of the JSON property the c# prop matches too.
public class MonthlyPerformance
{
public List<Type> Type { get; set; }
}
public class Type
{
public int id { get; set; }
public string countryId { get; set; }
public string Name { get; set; }
public List<Category> Category { get; set; }
public Type()
{
}
}
public class Category
{
public int id { get; set; }
public string countryId { get; set; }
public string name { get; set; }
public List<Fund> ConfigurationFund{ get; set; }
public Category()
{
}
}
public class Fund
{
public int id { get; set; }
public string countryId { get; set; }
public string name { get; set; }
public Fund()
{
}
}
回答5:
This is what I use for JSON deserialization...
using System.Web.Script.Serialization;
namespace blahblah
{
public partial class AccessTierService : ServiceBase
{
public static T ia_deserialize_json<T>(string json_string)
{
try
{
if ((String.Compare(json_string, null) == 0) ||
(String.Compare(json_string, "") == 0) ||
(String.Compare(json_string, String.Empty) == 0))
{
return default(T);
}
JavaScriptSerializer serializer = new JavaScriptSerializer();
return (T)serializer.Deserialize<T>(json_string);
}
catch (Exception)
{
return default(T);
}
}
}
}
and to call it...
login_request = ia_deserialize_json<ol_login_request>(body_string);
来源：https://stackoverflow.com/questions/8249454/how-do-deserialize-this-json-into-an-object