C#

//make sure curvelist has one curve
           if (zedGraphControl1.GraphPane.CurveList.Count <= 0)
               return;
           //Get first CurveItem in Graph
           LineItem curve = zedGraphControl1.GraphPane.CurveList[0] as LineItem;
           if (curve == null)
               return;
           // Get the PointPairList
           IPointListEdit list = curve.Points as IPointListEdit;
           // If this is null, it means the reference at curve.Points does not
           // support IPointListEdit, so we won't be able to modify it
           if (list == null)
               return;

           // Time is measured in seconds

           double time = (Environment.TickCount - tickStart) / 1000.0;


           // 3 seconds per cycle
           list.Add(time, dblLabel);

           // Keep the X scale at a rolling 30 second interval, with one
           // major step between the max X value and the end of the axis
           Scale xScale = zedGraphControl1.GraphPane.XAxis.Scale;
           if (time > xScale.Max - xScale.MajorStep)
           {
               xScale.Max = time + xScale.MajorStep;
               xScale.Min = xScale.Max - 30.0;
           }

           // Make sure the Y axis is rescaled to accommodate actual data
           zedGraphControl1.AxisChange();
           // Force a redraw
           zedGraphControl1.Invalidate();