Greetings, we have analyzed your requirement and you can achieve this by setting EnableZoom property as true in SfMaps as per the below code snippet.
When the mouse is scrolled up, the map is zoomed in. When the mouse is scrolled down, the map is zoomed out. You can place mouse in any position and do the zooming operation for that custom position.
Please refer below user documentation for more details about SfMaps zooming and panning.
If your requirement different this, please give more information about that. This would be helpful for us to give better solution in this.
Muneesh Kumar G.