Newtonsoft Jsonconverter not serializing properties when derived of list<>

Question

Consider the code below. When I try to serialize this by calling the 'SaveToFile' method the property 'Name' doens't get serialized.

Any ideas?

public class Subs
{
    public string Something { get; set; } = "smew";
}

public class Plep : List<Subs>
{

    public string Name { get; set; } = "smew";

    public void SaveToFile(string file)
    {

        using (StreamWriter wrt = new StreamWriter(file))
        {
            wrt.WriteLine(JsonConvert.SerializeObject(this, Formatting.Indented, new JsonSerializerSettings
            {
                TypeNameHandling = TypeNameHandling.All,
                //TypeNameAssemblyFormatHandling = TypeNameAssemblyFormatHandling.Simple,

            }));
        }
    }
}

How do you expect it to be serialized to JSON? As array or object with properties? These are incompatible and it seems that Newtonsoft falls back to the List/Array. — phuzi, Oct 14 '19 at 11:38
Why do you even **derive** from list? Usually you don´t need this. Instead just **use** a list, e.g. by exposing a `List`. — MakePeaceGreatAgain, Oct 14 '19 at 11:38
Looks like a duplicate of [How to serialize/deserialize a custom collection with additional properties using Json.Net](https://stackoverflow.com/q/14383736/3744182) and [How do I get json.net to serialize members of a class deriving from `List`?](https://stackoverflow.com/q/21265629/3744182) and [JSON serialize properties on class inheriting list](https://stackoverflow.com/q/35439335/3744182). — dbc, Oct 14 '19 at 17:52

score 2 · Accepted Answer · edited Oct 14 '19 at 11:38

2

Don't derive you class from List<> as mentioned here.

Change your class to:

public class Plep 
{
public string Name { get; set; } = "smew";
public List<Subs> Subs {get;set;}

public void SaveToFile(string file)
{

    using (StreamWriter wrt = new StreamWriter(file))
    {
        wrt.WriteLine(JsonConvert.SerializeObject(this, Formatting.Indented, new JsonSerializerSettings
        {
            TypeNameHandling = TypeNameHandling.All,
            //TypeNameAssemblyFormatHandling = TypeNameAssemblyFormatHandling.Simple,

        }));
    }
}

edited Oct 14 '19 at 11:38

phuzi

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answered Oct 14 '19 at 11:38

Neil

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For now this is the solution i'll be using. It isn't completely what I wanted though, I have to do something else now. I hope to elaborate some more in the near future. – Bas Visscher Oct 14 '19 at 13:05

Newtonsoft Jsonconverter not serializing properties when derived of list<>

1 Answers1