ASP.NET Core and Newtonsoft JSON.NET : how to force to fail on invalid fields?-CodePudding

We have a .NET Core 3.1 web app and use Newtonsoft JSON.NET serializer there registered for serializing/deserializing. But now we got stupid client who send us invalid JSON which contain fields which we don't have in our models. It's normal for JSON to ignore them, but I need to find way to create model state errors when deserializer finds invalid fields.

We have problem with optional fields so default validation won't help here.

CodePudding user response：

based on this doc try something like this

Class c = JsonConvert.DeserializeObject<List<Class>>("your string",
    new JsonSerializerSettings
    {
        Error = delegate(object sender, ErrorEventArgs args)
        {
            errors.Add(args.ErrorContext.Error.Message);
            args.ErrorContext.Handled = true;
        },
        Converters = { new IsoDateTimeConverter() }
    });

error handler: args.ErrorContext.Handled = {true/false};

CodePudding user response：

found solution

SerializerSettings.MissingMemberHandling = MissingMemberHandling.Error;

will throw error when my model doens't have fields from json. Bad naming I was thinking that it'll work vice versa.