SaveFileDialog saveFileDialog = new SaveFileDialog();
saveFileDialog.Filter = "PDF File (.pdf)|*.pdf";
bool? useClick = saveFileDialog.ShowDialog();
if (useClick == true)
{
var stream = saveFileDialog.OpenFile();
GrapeCity.Windows.SpreadSheet.Data.Margins printmar = new GrapeCity.Windows.SpreadSheet.Data.Margins();
printmar.Left = 10;
printmar.Right = 10;
printmar.Top = 20;
printmar.Bottom = 40;
GrapeCity.Windows.SpreadSheet.Data.PrintInfo printset = new GrapeCity.Windows.SpreadSheet.Data.PrintInfo();
printset.Margin = printmar;
gcSpreadSheet1.Sheets[0].PrintInfo = printset;
gcSpreadSheet1.SavePDF(stream, 0);
stream.Dispose();
}