API Json response to C# Object with capital case properties first letter

Question

I've made an API where after an Entity Framework elaboration I send an object serialized in Json.

My Object:

public class Package
{
    public int Items { get; set; }
    public string Code { get; set; }
    public string Description { get; set; }
    public double? Weight { get; set; }
    public string Size { get; set; }
    public string PackageType { get; set; }
}

The problem start when after recieve it (Xamarin app) the Json have the first letter lowercase, but I want deserialize it in the exact same class and it can't because the class have properties in capitalcase (C# standard). Now I'm using a horrible 'helper' class that have the properties in lowercase for translating it.

Any idea how to handle this and send the Json directly with capital case first letter?

Edit

I use ASP.NET web API Core and Newtonsoft.Json

In Xamarin app I use System.Text.Json

Dissolvent

Are you using asp.net web api core? – Despoliation

Are you using Newtonsoft.Json or System.Text.Json? – Rinee

Sorry, I didn't specify it... I use asp.net web api core and I use Newtonsoft.Json in the core API and System.Text.Json in Xamarin app – Dissolvent

Answer 1

By default, ASP.NET Core encodes all JSON properties names in camel case, to match JSON conventions (see the announcement of the change on GitHub).

If you want to keep the C# conventions, you need to change the default JSON serializer.

In your Startup.cs, configure the MVC part like this (ASP.Net Core 3.0):

services
    .AddMvc()
    .AddNewtonsoftJson(options =>
    {
        // don't serialize with CamelCase (see https://github.com/aspnet/Announcements/issues/194)
        options.SerializerSettings.ContractResolver = new JsonContractResolver();
    });

For ASP.NET Core 2.0 :

services
    .AddMvc()
    .AddJsonOptions(options =>
    {
        // don't serialize with CamelCase (see https://github.com/aspnet/Announcements/issues/194)
        options.SerializerSettings.ContractResolver = new DefaultContractResolver();
    });

Myriammyriameter

How are you using jsonSettings in the lambda that has options as a variable? – Fiacre

Sorry, that was a typo: you need to use options.SerializerSettings. I've edited the answer. – Breastpin

Answer 2

You have to change the default property naming policy on the json serialization options.

By default it's set to camel case but if you set it to null, the property names are to remain unchanged (or remain as you wrote on your class).

Simply add this to your Startup.cs:

services.AddControllers()
.AddJsonOptions(options =>
{
   options.JsonSerializerOptions.PropertyNamingPolicy = null;
});

Levison