private void OnSave() { var saveFileDialog = new SaveFileDialog(); saveFileDialog.FileName = $@"{DateTime.Now.ToString("yyyyMMdd")}"; saveFileDialog.AddExtension = true; saveFileDialog.DefaultExt = "json"; saveFileDialog.Filter = "JSONファイル|*.json"; saveFileDialog.InitialDirectory = Directory.GetParent(Assembly.GetExecutingAssembly().Location).ToString(); if (saveFileDialog.ShowDialog() ?? false) { using (var ofs = new StreamWriter(saveFileDialog.FileName, false, Encoding.UTF8)) { ofs.Write(ActionHistory.GetJson()); } } }