Question

So, I have some JSON I’m deserialising. Bear in mind I don’t have control of the data I’m getting; I just have to work with it as best I can.

It was going fairly well, until I ran into an issue where in an item ("z" below) can be two different types (see "z":[] and "z":{}) within the same item type (in the data I’m dealing with, things should be considered a Dictionary<string, FooType> after deserialisation…).

{
"things":{
    "1":{
        "x":123.45,
        "y":678.90,
        "z":{
                "2":true
            },
        "a":[
                1,
                2
            ]
        },
    "2":{
        "x":1414.23,
        "y":5656.78,
        "z":[
                true
            ],
        "a":[
                3
            ]
        }
    }
}

I’m pretty sure this is an output bug (i.e. the source is producing "z":[true] when it should produce "z":{"0":true}) because this is how "z":[true] is to be interpreted later in the application. However, as I said, I don’t have control of the data, and the issue is unlikely to be fixed any time soon.

I’ve tried having a member variable for each, but the naming conflict (from using [DataContract(Name = “z”)]) causes an exception (unsurprisingly).

How can I read both types of "z" into a common FooType? (Or equivalent, such as two subclasses of a common FooParentType that somehow get applied only in the correct cases…)

EDIT: I’d prefer to achieve the desired result as part of the deserialisation process, without preprcossing the string (although if there are no other ways, I’ll go there, I guess…)

I’m using C#, Mono, JSON.NET, and using code like so (compilable version on pastebin):

string jsonString = "{\"things\":{\"1\":{\"x\":123.45,\"y\":678.9,\"z\":{\"2\":true},\"a\":[1,2]},\"2\":{\"x\":1414.23,\"y\":5656.78,\"z\":[true],\"a\":[3]}}}";
RootType rt = JsonConvert.DeserializeObject<RootType>(jsonString);

With classes:

[DataContract]
class RootType
{
    [DataMember(IsRequired = true)]
    public Dictionary<string, FooType> things { get; set; }
}

[DataContract]
class FooType
{
    [DataMember(IsRequired = true)]
    public double x { get; set; }

    [DataMember(IsRequired = true)]
    public double y { get; set; }

    [DataMember(IsRequired = true)]
    public List<int> a { get; set; }

    // List<bool> zList and Dictionary<string, bool> zDict each only work for one case
    // but not the other, and having both causes a naming conflict
}

Answer 1

I had a similar issue and simply ran the string through a string.replace function to “correct” the data prior to deserializing.