c# - Why on Chart control the MouseWheel event never called ? And also the AxisViewChanged never called? -

i have on form1 designer windows forms chart control. in form1 constructor added:

chart1.chartareas[0].axisx.scaleview.zoomable = true; chart1.mousewheel += chart1_mousewheel; 

then have mousewheel event:

void chart1_mousewheel(object sender, mouseeventargs e)         {             messagebox.show("hi");         } 

and in designer added event axisviewchanged:

private void chart1_axisviewchanged(object sender, vieweventargs e)         {             painttocalaculate = true;             chart1.invalidate();         } 

but using breakpoint in mousewheel event or on axisviewchanged event it's never , stop there.