Hi Andreas,
You can intercept the data zoom tool end drag event:
NDataZoomTool dzt = new NDataZoomTool();
dzt.EndDrag += new EventHandler(dzt_EndDrag);
void dzt_EndDrag(object sender, EventArgs e)
{
// do something on end drag
}
Hope this helps - let me know if you meet any problems.
Best regards,
Bob