using System.IO; namespace System.Net.Http { /// public class HttpPlatformHelper : IHttpPlatformHelper { const string DefaultUserAgent = "Mozilla/5.0 (Windows Phone 10.0; Android 4.2.1; Microsoft; Lumia 950) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2486.0 Mobile Safari/537.36 Edge/14.14263"; public virtual string UserAgent => DefaultUserAgent; public (string filePath, string mime)? TryHandleUploadFile(Stream fileStream) => null; } }