test.cs

public static SmartDocument ExtractSmartDocument(string DocumentName) {

  SmartDocument smartDocument = new SmartDocument();

  using (TXTextControl.ServerTextControl tx = new TXTextControl.ServerTextControl()) {

    tx.Create();

    // the load PDF document
    TXTextControl.LoadSettings loadSettings = new LoadSettings();
    tx.Load("App_Data/" + DocumentName,
      TXTextControl.StreamType.AdobePDF,
      loadSettings);

    // loop through all attachments to find the original document
    // and the annotations
    foreach (EmbeddedFile file in loadSettings.EmbeddedFiles) {

      if (file.FileName == "original.tx")
        smartDocument.Document = Convert.ToBase64String((byte[])file.Data);

      if (file.FileName == "annotations.json")
        smartDocument.Annotations = System.Text.Encoding.UTF8.GetString((byte[])file.Data);
    }

    smartDocument.Name = DocumentName;
  }

  return smartDocument;
}