Exactly how to handle the event would depend on what platform you use. For example, if you use WPF, you can handle MouseWheel event on the Window object like this:
Code: HTML/ASPX
<Window ..... MouseWheel="Window_MouseWheel" ...>
....
</Window>
Inside your Window_MouseWheel event you can then do:
Code: C#
if (Keyboard.IsKeyDown(Key.LeftCtrl))
{
if (e.Delta > 0)
webView.ZoomFactor = webView.ZoomFactor * 1.25;
else if (e.Delta < 0)
webView.ZoomFactor = webView.ZoomFactor / 1.25;
}
If you use Windows.Forms, then the code would be different. However the key part is to set the WebView's ZoomFactor property.
Thanks!