how is content of XPSDocument specified?

relative to the line:
XpsDocument xpsDocument = new XpsDocument("C:\\FixedDocumentSequence.xps", FileAccess.ReadWrite);
I could not see anything specifying what content should go into the XPSDocument.

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* ID: 8da622e3-6ab9-d565-b8e9-42ae7c313319
* Version Independent ID: 73a68a62-3a8b-f635-2a4e-79e3d36ea98c
* Content: [PrintDialog Class (System.Windows.Controls)](https://docs.microsoft.com/en-us/dotnet/api/system.windows.controls.printdialog?view=netframework-4.7.2)
* Content Source: [xml/System.Windows.Controls/PrintDialog.xml](https://github.com/dotnet/dotnet-api-docs/blob/master/xml/System.Windows.Controls/PrintDialog.xml)
* Product: **dotnet-api**
* GitHub Login: @dotnet-bot
* Microsoft Alias: **dotnetcontent**