protected override void OnPreviewMouseMove(MouseEventArgs e)
{
if (this.IsMouseCaptured)
{
// Get the new mouse position.
Point mouseDragCurrentPoint = e.GetPosition(this.ScrollBoard);
// Determine the new amount to scroll.
Point delta = new Point(
(mouseDragCurrentPoint.X > this.mouseDragStartPoint.X) ?
-(mouseDragCurrentPoint.X - this.mouseDragStartPoint.X) :
(this.mouseDragStartPoint.X - mouseDragCurrentPoint.X),
(mouseDragCurrentPoint.Y > this.mouseDragStartPoint.Y) ?
-(mouseDragCurrentPoint.Y - this.mouseDragStartPoint.Y) :
(this.mouseDragStartPoint.Y - mouseDragCurrentPoint.Y));
// Scroll to the new position.
ScrollBoard.ScrollToHorizontalOffset(this.scrollStartOffset.X + delta.X);
ScrollBoard.ScrollToVerticalOffset(this.scrollStartOffset.Y + delta.Y);
}
base.OnPreviewMouseMove(e);
}
