Clearing data points in MSChart is known to be very slow. http://connect.microsoft.com/VisualStudio/feedback/details/596212/performance-problem-in-mschart-datapointcollection-clear
However, there is a work around for this problem. Suggested work around from link stated above is as below:
public void ClearPointsQuick()
while (Points.Count > 0)
Points.RemoveAt(Points.Count - 1);
Extension method implementation is as below:
internal static class MSChartExtension
public static void ClearPoints(this Series sender)
while (sender.Points.Count > 0)
sender.Points.RemoveAt(sender.Points.Count - 1);
(NOTE 1) I added one additional line Points.Clear() at the end of the function to ensure the chart axis updated correctly on next plot. Without adding this line, I observed that previous axis settings will be used when plotting new data points right after calling ClearPoints().
MSChart Extension: An extension package for MSChart component which contains this fixes and others features.
31/03/2012: Added additional line to force axis update on next plot (NOTE 1).
12/03/2012: Initial released.