Hseyin Tfekilerli

namespace MoveAndZoom
{
    using System.Windows;
    using System.Windows.Input;
    using System.Windows.Media;

    public partial class Window1 : Window
    {
        private TranslateTransform panTransform;
        private ScaleTransform zoomTransform;
        private TransformGroup renderTransform;

        Point p;
        public Window1()
        {
            InitializeComponent();

            panTransform = new TranslateTransform();
            zoomTransform = new ScaleTransform();
            renderTransform = new TransformGroup();

            renderTransform.Children.Add(panTransform);
            renderTransform.Children.Add(zoomTransform);

            Img.RenderTransform = renderTransform;
        }

        private void Img_MouseWheel(object sender, MouseWheelEventArgs e)
        {
            var zoomFactor = e.Delta > 0 ? 1.1 : 0.9;

            zoomTransform.ScaleX *= zoomFactor;
            zoomTransform.ScaleY *= zoomFactor;
        }

        private void Img_MouseMove(object sender, MouseEventArgs e)
        {
            Point x = e.GetPosition(ImageHolder);
            if (e.LeftButton == MouseButtonState.Pressed)
            {
                panTransform.X += (x.X - p.X) / zoomTransform.ScaleX;
                panTransform.Y += (x.Y - p.Y) / zoomTransform.ScaleY;
            }
            p = x;
        }

        private void Img_MouseDown(object sender, MouseButtonEventArgs e)
        {
            Img.CaptureMouse();
            p = e.GetPosition(ImageHolder);
        }

        private void Img_MouseUp(object sender, MouseButtonEventArgs e)
        {
            Img.ReleaseMouseCapture();
        }
    }
}