private async void loadFileAsync(String location, SupportFormat format) { string handler = "KLEditor.Utils." + TitleCase(format.ToString()) + "Handler"; Type type = Type.GetType(handler); var con = type.GetConstructor(new Type[] { typeof(String) }); file = con.Invoke(new Object[] { location }) as IFileOperator; var stream = await file.GetInputStream(); richTextBox.Invoke(new Action(() => { using (stream) { richTextBox.LoadFile(stream, file.RTBType); } })); }