private void btnZoomOut_Click(object sender, RoutedEventArgs e)
{
// Grab the MapPrinterLayer and adjust the extent
PrinterInteractiveOverlay printerOverlay = (PrinterInteractiveOverlay)Map1.InteractiveOverlays["PrintPreviewOverlay"];
MapPrinterLayer mapPrinterLayer = ((MapPrinterLayer)(printerOverlay.PrinterLayers["MapLayer"]));
// Here we snap the current scale to the default zoomLevelSet when we zoom in
ZoomLevelSet zoomLevelSet = new ZoomLevelSet();
double newScale = ZoomLevelSet.GetHigherZoomLevelScale(MapUtil.GetScale(mapPrinterLayer.MapExtent, (float)mapPrinterLayer.GetBoundingBox().Width, mapPrinterLayer.MapUnit), zoomLevelSet);
mapPrinterLayer.MapExtent = MapUtil.ZoomToScale(newScale, mapPrinterLayer.MapExtent, mapPrinterLayer.MapUnit, (float)mapPrinterLayer.GetBoundingBox().Width, (float)mapPrinterLayer.GetBoundingBox().Height);
Map1.Refresh();
}