在PageSetupDialog中设置默认纸张大小

试试这个:

     PrinterSettings printerSettings = new PrinterSettings();

     IEnumerable<PaperSize> paperSizes = printerSettings.PaperSizes.Cast<PaperSize>();

     PaperSize sizeA4 = paperSizes.First<PaperSize>(size => size.Kind == PaperKind.A4); // setting paper size to A4 size

     PageSetupDialog pageSetupDialog = new PageSetupDialog();

     pageSetupDialog.PageSettings = new PageSettings() { PaperSize = sizeA4 };