Facebook.FacebookMediaObject.SetValue C# (CSharp) Method

        public FacebookMediaObject SetValue(byte[] value)
        {
            _value = value;
            return this;
        }

 private void Window_Loaded(object sender, RoutedEventArgs e)
 {
     // upload to facebook
     FacebookMediaObject image = new FacebookMediaObject
     {
         FileName = imgPath,
         ContentType = "image/jpeg"
     };
     byte[] fileBytes = File.ReadAllBytes(imgPath);
     image.SetValue(fileBytes);
     IDictionary<string, object> upload = new Dictionary<string, object>();
     upload.Add("name", imgName);
     upload.Add("message", imgMsg);
     upload.Add("@file.jpg", image);
     fb.UploadProgressChanged += uploadProgressChanged;
     fb.PostAsync("/me/photos", new Dictionary<string, object> {{"source", image}});
 }