var url = "https://onesignal.com/api/v1/notifications?app_id=8c8e38ee-443a-4684-b6fa-6b932f8fc572";
var httpRequest = (HttpWebRequest)WebRequest.Create(url);
httpRequest.Headers["Authorization"] = OneSignalNotificationKey;
var httpResponse = (HttpWebResponse)httpRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
var result = streamReader.ReadToEnd();
}
Console.WriteLine(httpResponse.StatusCode);