C# 4 and .NET 4

1090 ❘ ChaPTer 37 creAtinG dOcuments with wpf
To create an XPS document, you use the XpsDocument class from the namespace System.Windows
.Xps.Packaging. To use this class, you will need to reference the assembly ReachFramework as
well. With this class you can add a thumbnail (AddThumbnail()) and fixed document sequences
(AddFixedDocumentSequence()) to the document, as well as digitally sign the document. A fixed
document sequence is written by using the interface IXpsFixedDocumentSequenceWriter that in turn uses
an IXpsFixedDocumentWriter to write the document within the sequence.
If a FixedDocument already exists, there’s an easier way to write the XPS document. Instead of adding
every resource and every document page, you can use the class XpsDocumentWriter from the namespace
System.Windows.Xps. For this class the assembly System.Printing must be referenced.
With the following code snippet you can see the handler to create the XPS document. First, a filename for
the menu plan is created that uses a week number in addition to the name menuplan. The week number
is calculated with the help of the GregorianCalendar class. Then the SaveFileDialog is opened to
let the user overwrite the created filename and select the directory where the file should be stored. The
SaveFileDialog class is defined in the namespace Microsoft.Win32 and wraps the native file dialog.
Then a new XpsDocument is created where the filename is passed to the constructor. Recall that the XPS
file uses a ZIP format to compress the content. With the CompressionOption you can specify whether the
compression should be optimized on time or space.
Next, an XpsDocumentWriter is created with the help of the static method XpsDocument.
CreateXpsDocumentWriter(). The Write method of the XpsDocumentWriter is overloaded to accept
different content or content parts to write the document. Examples of acceptable options with the Write()
method are FixedDocumentSequence, FixedDocument, FixedPage, string, and a DocumentPaginator.
In the sample code, only the fixedDocument that was created earlier is passed:
private void OnCreateXPS(object sender, RoutedEventArgs e)
{
var c = new GregorianCalendar();
int weekNumber = c.GetWeekOfYear(menus[0].Day,
CalendarWeekRule.FirstFourDayWeek, DayOfWeek.Monday);
string fileName = String.Format("menuplan{0}", weekNumber);
var dlg = new SaveFileDialog
{
FileName = fileName,
DefaultExt = "xps",
Filter = "XPS Documents|*.xps|All Files|*.*",
AddExtension = true
};
if (dlg.ShowDialog() == true)
{
XpsDocument doc = new XpsDocument(dlg.FileName, FileAccess.Write,
CompressionOption.Fast);
XpsDocumentWriter writer = XpsDocument.CreateXpsDocumentWriter(doc);
writer.Write(fixedDocument);
doc.Close();
}
}
code snippet CreateXps/DocumentPage.xaml.cs
By running the application to store the XPS document, you can view the document with an XPS viewer, as
shown in Figure 37-14.
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