SaveFileDialog saveFileDialog = new SaveFileDialog();
saveFileDialog.Filter = "Excel File (.xlsx)|*.xlsx";
bool? useClick = saveFileDialog.ShowDialog();
if (useClick == true)
{
var stream = saveFileDialog.OpenFile();
gcSpreadSheet1.SaveExcel(stream, GrapeCity.Windows.SpreadSheet.Data.ExcelFileFormat.XLSX);
//gcSpreadSheet1.SaveExcel(stream, GrapeCity.Windows.SpreadSheet.Data.ExcelFileFormat.XLSX, GrapeCity.Windows.SpreadSheet.Data.ExcelSaveFlags.DataOnly);
//gcSpreadSheet1.SaveExcel(stream, GrapeCity.Windows.SpreadSheet.Data.ExcelFileFormat.XLSX, GrapeCity.Windows.SpreadSheet.Data.ExcelSaveFlags.DataOnly, "12Test9");
//gcSpreadSheet1.SaveExcel(stream, GrapeCity.Windows.SpreadSheet.Data.ExcelFileFormat.XLSX, "12Test9");
stream.Dispose();
}