Decimal serialization JSON to Web API - json

Question

I have problem getting json data containing even float: 10.0.
AngularJS
var replenishAccount = { ReloadThresholdAmount: parseFloat(vm.account.ReloadThresholdAmount), ReloadAmount: parseFloat(vm.account.ReloadAmount) };
var webApiUrl = "https://localhost:44301";
$http({ method: 'PATCH', url: webApiUrl + '/api/account/patch/' + vm.account.ID, data: angular.toJson(replenishAccount)})
JSON
{"ReloadThresholdAmount": 10.2, "ReloadAmount": 10}
What I need is
{"ReloadThresholdAmount": 10.2, "ReloadAmount": 10.0}
If I do .toFix(2), I get the string but web api expects decimal.
{"ReloadThresholdAmount": "10.2", "ReloadAmount": "10.0"}
Basically, Web Api complains that it cannot be string or integer.
Web API, I am using Delta. Those 2 amounts are double in .NET.
[Route("Patch/{id}")]
public IHttpActionResult Patch(int id, Delta<Account> account)
{
if (account == null)
return BadRequest();
Account accountFromDb = Account.GetInstanceByID(CurrentUser, id);
account.Patch(accountFromDb);
accountFromDb.Save(CurrentUser);
return Ok(account);
}

Answer 1

Json.NET, which is the out of the box deserializer for Web API correctly deserialize the {"ReloadThresholdAmount": 10.2, "ReloadAmount": 10} JSON into decimals.
e.g. your class should be
public class ReplenishAccount
{
public decimal ReloadThresholdAmount;
public decimal ReloadAmount;
}
Then
var account = JsonConvert.DeserializeObject<ReplenishAccount>(json);
Console.WriteLine("ReloadThresholdAmount: {0:0.0}; ReloadAmount: {1:0.0}", account.ReloadThresholdAmount, account.ReloadAmount);
works as expected (fiddle: https://dotnetfiddle.net/YX5FsR).
In Web API, you would use [FromBody] attribute, and it should deserialize the same exact way.

Answer 2

As it turns out, it is specific to deserializing Delta object. Delta is meant to used with ODataMediaTypeFormatter and using it with JSON.NET (NewtonSoft) is buggy with integer etc. Many SO posts supported this argument.
I finally used Asp.net Delta Json Deserialization and added this to web config. This serializes Delta in a breeze, after hours of debugging and researching.