ChartMouseWheelEventArgs

 using cAlgo.API;
 namespace cAlgo
 {
     // This example shows how to use the Chart ChartMouseWheelEventArgs
     // ChartMouseWheelEventArgs derives from ChartMouseEventArgs
     [Indicator(IsOverlay = true, TimeZone = TimeZones.UTC, AccessRights = AccessRights.None)]
     public class ChartMouseWheelEventArgsSample : Indicator
     {
         protected override void Initialize()
         {
             Chart.MouseWheel += Chart_MouseWheel;
         }
         private void Chart_MouseWheel(ChartMouseWheelEventArgs obj)
         {
             var text = string.Format("Wheel Delta: {0}", obj.Delta);
             Chart.DrawStaticText("Wheel", text, VerticalAlignment.Top, HorizontalAlignment.Right, Color.Red);
         }
         public override void Calculate(int index)
         {
         }
     }
 }

 import clr
 clr.AddReference("cAlgo.API")
 from cAlgo.API import *
 class Test():    
     def initialize(self):
         api.Chart.MouseWheel += self.on_chart_mouse_wheel
     def on_chart_mouse_wheel(self, args):
         text = f"Wheel Delta: {args.Delta}"
         api.Chart.DrawStaticText("Wheel", text, VerticalAlignment.Top, HorizontalAlignment.Right, Color.Red)