C#在打印窗体的时候总是出席那下面这种问题

Question

这个打印方面的代码是：
printTicket = new TicketPrintWindowcs(
strStartStation, strTrainCode, strArriveStation,
strStartTime, strRailwayCarruageNumber,strSeatNumber, strprice,
strName, strPaperNum, strSeatType, strCouchetteType, strDateOfTravel);
printTicket.Show();
PageSettings ps = new PageSettings();
PD_TicketDoc.DefaultPageSettings = ps;
ps.PaperSize = new PaperSize("NewSize", 400, 273);
PD_PrintTicket.Document = PD_TicketDoc;
PD_TicketDoc.Print();
printTicket.Close();
打印事件代码是：
private void PD_TicketDoc_PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e)
{
Image myFormImage;
myFormImage = new Bitmap(printTicket.Width, printTicket.Height);
Graphics g = Graphics.FromImage(myFormImage);
g.CopyFromScreen(printTicket.Location.X, printTicket.Location.Y, 0, 0, printTicket.Size);
e.Graphics.DrawImage(myFormImage, 0, 0);
printTicket.Close();
}
为什么会这样呢，窗体在show的时候为什么没有显示完全呢