azure-functions-data.json

{
    "MyData": "Kevin Bronsdijk",
}

azure-functions.cs

#r "Newtonsoft.Json"

using System;
using System.Net;
using System.Threading.Tasks;
using Newtonsoft.Json;

public static async Task<object> Run(HttpRequestMessage req, TraceWriter log)
{
    string jsonContent = await req.Content.ReadAsStringAsync();
    dynamic data = JsonConvert.DeserializeObject(jsonContent);

    if (data.MyData == null ) {
        return req.CreateResponse(HttpStatusCode.BadRequest, new {
            error = "Input incorrect!"
        });
    }
    else
    {
        return req.CreateResponse(HttpStatusCode.OK, new {
            result = $"Complex result {data.MyData}!"
        });
    }
}