JsonConvert.DeserializeObject array of arrays

Question

This is similar to other postings, but my variation is that my json object begins as an array of arrays, and I can't get it to deserialize.

class Program
{
    static void Main(string[] args)
    {
        var json = @"[[{""f1"":1, ""f2"":2}]]";
        var obj = JsonConvert.DeserializeObject<RootObject[]>(json);
    }
}

public class RootObject
{
    public List<InnerObject> InnerObjects { get; set; } 
}

public class InnerObject
{
    public int f1 { get; set; }
    public int f2 { get; set; }
}

I've also tried

JsonConvert.DeserializeObject<List<RootObject>>(json);

and various other variations. The exception text begins "Cannot deserialize the current JSON array (e.g. [1,2,3]) into type 'jsontest.RootObject' because the type requires a JSON object (e.g. {"name":"value"}) to deserialize correctly."

Answer 1

Your JSON corresponds to a List<List<InnerObject>> not a RootObject[]. (For the latter, the JSON would need to look like this: [{ "InnerObjects" : [{"f1": 1, "f2": 2}] }]).

Try deserializing like this:

var list = JsonConvert.DeserializeObject<List<List<InnerObject>>>(json);

Fiddle: https://dotnetfiddle.net/ELnmfg