Adding Multitouch Support to .NET PDF Viewer.

Q: I am developing a tablet implementation of our PDF software, which runs on a Windows 7 tablet. Our customer has requested some touch interface functionality, at this point specifically two finger scrolling and zooming. I do not see events for these inputs in the documentation for your .NET implementation . I am curious if I could use PDFNet .NET control to provide our customer with some touch functionality. Thank you for your support.


The best option would be to use ‘pdftron.PDF.PDFViewCtrlWPF’ which is included as part of ‘PDFNet for .Net 4+’ (

As a starting point, please take a look at PDFNet/Samples/PDFViewWPF sample.

WPF 4 includes support for touch events as described in the following article:

For example, a basic pinch to zoom could look as follows:

void PDFView_ManipulationDelta(object sender, ManipulationEventArgs e)


var deltaManipulation = e.DeltaManipulation;


double dDelta = 0;

if (deltaManipulation.Scale.X > deltaManipulation.Scale.Y) dDelta = deltaManipulation.Scale.X;

else dDelta = deltaManipulation.Scale.Y;

double newZoom = this.GetZoom() * dDelta;

this.CurrentZoom = newZoom;


this.SetVScrollPos(this.GetVScrollPos() - deltaManipulation.Translation.Y * 1.25);

this.SetHScrollPos(this.GetHScrollPos() - deltaManipulation.Translation.X * 1.25);