Deserializing an array of different object types

Question

Using the Json.NET library, I'm having trouble deserializing some json returned as an array. The json is an array containing some paging information as an object and array of country objects. Here's a sample of the returned json:

[
    {
        "page": 1,
        "pages": 6,
        "per_page": "50",
        "total": 262
    },
    [
        {
            "id": "ABW",
            "iso2Code": "AW",
            "name": "Aruba",
            "region": {
                "id": "LCN",
                "value": "Latin America & Caribbean (all income levels)"
            },
            "adminregion": {
                "id": "",
                "value": ""
            },
            "incomeLevel": {
                "id": "NOC",
                "value": "High income: nonOECD"
            },
            "lendingType": {
                "id": "LNX",
                "value": "Not classified"
            },
            "capitalCity": "Oranjestad",
            "longitude": "-70.0167",
            "latitude": "12.5167"
        }
    ]
]

I am attempting to deserialize to the following types:

class CountriesQueryResults
{
    public PagingInfo PageInfo { get; set; }
    public List<CountryInfo> Countries { get; set; }
}

class PagingInfo
{
    public int Page { get; set; }
    public int Pages { get; set; }
    [JsonProperty("per_page")]  
    public int ResultsPerPage { get; set; }
    public int Total { get; set; }
}

class CountryInfo
{
    public string Id { get; set; }
    public string Iso2Code { get; set; }
    public string Name { get; set; }
    public string Longitude { get; set; }
    public string Latitude { get; set; }
    public string CapitalCity { get; set; }
    public CompactIdentifier Region { get; set; }
    public CompactIdentifier AdminRegion { get; set; }
    public CompactIdentifier IncomeLevel { get; set; }
    public CompactIdentifier LendingType { get; set; }  
}

class CompactIdentifier
{
    public string Id { get; set; }
    public string Value { get; set; }
}

I am calling DeserializeObject as so:

var data = JsonConvert.DeserializeObject<List<CountriesQueryResults>>(response);

I am getting the following error:

Cannot deserialize the current JSON object (e.g. {"name":"value"}) into type 'CountriesQueryResults' because the type requires a JSON array (e.g. [1,2,3]) to deserialize correctly.

I have been trying to get the answer from the documentation but I can't seem to figure it out. Any help would be appreciated.

http://stackoverflow.com/a/18192564/95573 – SwDevMan81 Feb 14 '15 at 20:49 — SwDevMan81, Feb 14 '15 at 20:49

EZI · Accepted Answer · 2015-02-14T22:08:55.980

Since your json is like this [ {....} , [{....}] ], You can only deserialize it to an object array(Where first item is an object and second, another array).

This simplest way I think to convert it to a c# object is:

var jArr = JArray.Parse(jsonstr);
var pageInfo = jArr[0].ToObject<PagingInfo>();
var countryInfos = jArr[1].ToObject<List<CountryInfo>>();

Class definitions would be:

public class PagingInfo
{
    public int page { get; set; }
    public int pages { get; set; }
    [JsonProperty("per_page")]
    public int ResultsPerPage { get; set; }
    public int total { get; set; }
}

public class Region
{
    public string id { get; set; }
    public string value { get; set; }
}

public class AdminRegion
{
    public string id { get; set; }
    public string value { get; set; }
}

public class IncomeLevel
{
    public string id { get; set; }
    public string value { get; set; }
}

public class LendingType
{
    public string id { get; set; }
    public string value { get; set; }
}

public class CountryInfo
{
    public string id { get; set; }
    public string iso2Code { get; set; }
    public string name { get; set; }
    public Region region { get; set; }
    public AdminRegion adminregion { get; set; }
    public IncomeLevel incomeLevel { get; set; }
    public LendingType lendingType { get; set; }
    public string capitalCity { get; set; }
    public string longitude { get; set; }
    public string latitude { get; set; }
}

PS: You can change the property names' first char to Uppercase if you want. I used http://json2csharp.com/ to automatically generate those classes.

Deserializing an array of different object types

1 Answers1