Jan 07, 2019 03:00 PM|mgebhard|LINK
This was explained with source code in your other thread.
The JSON is returned as a stream as a result of invoking a REST endpoint.
result = await response.Content.ReadAsAsync<JsonResponse>();
Again, the service documentation should explain how to make a proper request!
Edit, if you are trying to read the JSON from a file for testing then...
string img = string.Empty;
using (StreamReader file = File.OpenText("data.json"))
JsonSerializer serializer = new JsonSerializer();
JsonResponse response = (JsonResponse)serializer.Deserialize(file, typeof(JsonResponse));
img = response.img;