Windows Forms Printing

FAQ Home

1. How do I print a form?
2. How do I display the PrintPreview maximized and control its zooming?
 

1 How do I print a form?

I am afraid there is not a very easy way to print a form. You may implement this function with the steps below:

1) Add a print function to your application.

To do this, you should add a PrintDocument component to your application.
Please drag a PrintDocument from the tool box to your form. After that, you
should create a PrintDialog and add the code to print the document.

          private void buttonPrint_Click(object sender, System.EventArgs e)
          {
               PrintDialog printDialog1 = new PrintDialog();
               printDialog1.Document = printDocument1;
               DialogResult result = printDialog1.ShowDialog();
               if (result == DialogResult.OK)
               {
                    printDocument1.Print();
               }
          }

For detailed information about print framework, please see "Windows Forms Print Support" in the MSDN (October 2001).

2) Draw the form when printing.

This step is a little complex. You should handle the PrintPage of the printDocument1 and draw the form to the printer device. In the event you may copy the form to an image and then draw it to the printer device.

          private void printDocument1_PrintPage(object sender,
System.Drawing.Printing.PrintPageEventArgs e)
          {
               Graphics graphic = this.CreateGraphics();
               Size s = this.Size;
               Image memImage = new Bitmap(s.Width, s.Height, graphic);
               Graphics memGraphic = Graphics.FromImage(memImage);
               IntPtr dc1 = graphic.GetHdc();
               IntPtr dc2 = memGraphic.GetHdc();
               BitBlt(dc2, 0, 0, this.ClientRectangle.Width,
this.ClientRectangle.Height, dc1, 0, 0, 13369376);
               graphic.ReleaseHdc(dc1);
               memGraphic.ReleaseHdc(dc2);
               e.Graphics.DrawImage(memImage,0,0);
          }

The above referenced the article "Screen Capturing a Form in .NET - Using
GDI in GDI+" by Michael Gold. You may find it at:
http://www.c-sharpcorner.com/Graphics/ScreenCaptFormMG.asp

3) Declare the API function.

Please note the BitBlt function used in Step 2. It is an unmanaged function. You should use DllImportAttribute attribute to import it to your code. Although, this is the Step 3, you may perform this step any time.

          [System.Runtime.InteropServices.DllImportAttribute("gdi32.dll")]
          private static extern bool BitBlt(
               IntPtr hdcDest, // handle to destination DC
               int nXDest, // x-coord of destination upper-left corner
               int nYDest, // y-coord of destination upper-left corner
               int nWidth, // width of destination rectangle
               int nHeight, // height of destination rectangle
               IntPtr hdcSrc, // handle to source DC
               int nXSrc, // x-coordinate of source upper-left corner
               int nYSrc, // y-coordinate of source upper-left corner
               System.Int32 dwRop // raster operation code
               );

For more information about DllImportAttribute attribute please see:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfSystemRuntimeInteropServicesDllImportAttributeClassTopic.asp

(from Lion Shi (lion_noreply@microsoft.com) on microsoft.public.dotnet.framework.windowsforms)
 

2 How do I display the PrintPreview maximized and control its zooming?

You can use the WindowState property of the PrintPreviewDialog class to bring the PrintPreview maximized. To handle zooming, the PrintPreviewDialog has a property, PrintPreviewControl. PrintPreviewControl owns a Zoom property that allows you to set the zoom factor of the PrintPreview.