Printing a WPF FlowDocument - wpf

Question

I'm building a demo app in WPF, which is new to me. I'm currently displaying text in a FlowDocument, and need to print it.
The code I'm using looks like this:
PrintDialog pd = new PrintDialog();
fd.PageHeight = pd.PrintableAreaHeight;
fd.PageWidth = pd.PrintableAreaWidth;
fd.PagePadding = new Thickness(50);
fd.ColumnGap = 0;
fd.ColumnWidth = pd.PrintableAreaWidth;
IDocumentPaginatorSource dps = fd;
pd.PrintDocument(dps.DocumentPaginator, "flow doc");
fd is my FlowDocument, and for now I'm using the default printer instead of allowing the user to specify print options. It works OK, except that after the document prints, the FlowDocument displayed on screen has changed to to use the settings I specified for printing.
I can fix this by manually resetting everything after I print, but is this the best way? Should I make a copy of the FlowDocument before I print it? Or is there another approach I should consider?

Answer 1

yes, make a copy of the FlowDocument before printing it. This is because the pagination and margins will be different. This works for me.
private void DoThePrint(System.Windows.Documents.FlowDocument document)
{
// Clone the source document's content into a new FlowDocument.
// This is because the pagination for the printer needs to be
// done differently than the pagination for the displayed page.
// We print the copy, rather that the original FlowDocument.
System.IO.MemoryStream s = new System.IO.MemoryStream();
TextRange source = new TextRange(document.ContentStart, document.ContentEnd);
source.Save(s, DataFormats.Xaml);
FlowDocument copy = new FlowDocument();
TextRange dest = new TextRange(copy.ContentStart, copy.ContentEnd);
dest.Load(s, DataFormats.Xaml);
// Create a XpsDocumentWriter object, implicitly opening a Windows common print dialog,
// and allowing the user to select a printer.
// get information about the dimensions of the seleted printer+media.
System.Printing.PrintDocumentImageableArea ia = null;
System.Windows.Xps.XpsDocumentWriter docWriter = System.Printing.PrintQueue.CreateXpsDocumentWriter(ref ia);
if (docWriter != null && ia != null)
{
DocumentPaginator paginator = ((IDocumentPaginatorSource)copy).DocumentPaginator;
// Change the PageSize and PagePadding for the document to match the CanvasSize for the printer device.
paginator.PageSize = new Size(ia.MediaSizeWidth, ia.MediaSizeHeight);
Thickness t = new Thickness(72); // copy.PagePadding;
copy.PagePadding = new Thickness(
Math.Max(ia.OriginWidth, t.Left),
Math.Max(ia.OriginHeight, t.Top),
Math.Max(ia.MediaSizeWidth - (ia.OriginWidth + ia.ExtentWidth), t.Right),
Math.Max(ia.MediaSizeHeight - (ia.OriginHeight + ia.ExtentHeight), t.Bottom));
copy.ColumnWidth = double.PositiveInfinity;
//copy.PageWidth = 528; // allow the page to be the natural with of the output device
// Send content to the printer.
docWriter.Write(paginator);
}
}

Answer 2

You can use the code from the URL below, it wraps the flow document in a fixed document and prints that, the big advantage is that you can use it to add margin, headers and footers.
https://web.archive.org/web/20150502085246/http://blogs.msdn.com:80/b/fyuan/archive/2007/03/10/convert-xaml-flow-document-to-xps-with-style-multiple-page-page-size-header-margin.aspx

Answer 3

The following works with both text and non-text visuals:
//Clone the source document
var str = XamlWriter.Save(FlowDoc);
var stringReader = new System.IO.StringReader(str);
var xmlReader = XmlReader.Create(stringReader);
var CloneDoc = XamlReader.Load(xmlReader) as FlowDocument;
//Now print using PrintDialog
var pd = new PrintDialog();
if (pd.ShowDialog().Value)
{
CloneDoc.PageHeight = pd.PrintableAreaHeight;
CloneDoc.PageWidth = pd.PrintableAreaWidth;
IDocumentPaginatorSource idocument = CloneDoc as IDocumentPaginatorSource;
pd.PrintDocument(idocument.DocumentPaginator, "Printing FlowDocument");
}

Answer 4

I am also generating a WPF report off a Flow document, but I am purposely using the flow document as a print preview screen. I there for want the margins to be the same. You can read about how I did this here.
In your scenario I'm thinking why not just make a copy of your settings, instead of the entire flow document. You can then re-apply the settings if you wish to return the document back to it's original state.