Code

private void diagram_DoubleClicked(object sender, DiagramEventArgs e)
{
	MemoryStream ms = new MemoryStream();
	Package pkg = Package.Open(ms, FileMode.Create, FileAccess.ReadWrite);
	string pack = "pack://temp.xps";
	PackageStore.AddPackage(new Uri(pack), pkg);
	XpsDocument doc = new XpsDocument(pkg, CompressionOption.NotCompressed, pack);
	XpsSerializationManager rsm = new XpsSerializationManager(new XpsPackagingPolicy(doc), false);
	rsm.SaveAsXaml(diagram.DocumentPaginator);
	documentViewer1.Document = doc.GetFixedDocumentSequence(); ;
}