performance problem in MSChart DataPointCollection.Clear()

performance problem in MSChart DataPointCollection.Clear() by selfcomposed

Closed

as Won't Fix Help for as Won't Fix

Type:	Bug
ID:	596212
Opened:	9/8/2010 12:42:25 PM
Access Restriction:	Public

Workaround(s)

view

User(s) can reproduce this bug

The MSChart DataPointCollection.Clear() method is quite slow, taking about 5 seconds to delete 70k elements. It calls ClearItems(), which removes items from the *beginning* of the list until the list is empty.

protected override void ClearItems()
{
    this.SuspendUpdates();
    while (base.Count > 0)
    {
        this.RemoveItem(0);
    }
    this.ResumeUpdates();
}

Details (expand)

.NET Framework 4

Fill a DataPointCollection with many elements, then Clear()

English

Windows XP

English

slow

fast.

Recode ClearItems() to remove items from the *end* of the list.

protected override void ClearItems()
{
    this.SuspendUpdates();
    while (base.Count > 0)
    {
        this.RemoveItem(base.Count-1); // remove from end
    }
    this.ResumeUpdates();
}

0 attachments

Posted by Pablo1397 on 8/8/2012 at 3:40 AM

For better performance Microsoft has to code in the class "ChartElementCollection<T>"

protected override void ClearItems()
{
    this.SuspendUpdates();
    while (base.Count > 0)
    {
        this.RemoveItem(base.Count - 1);
    }
    this.ResumeUpdates();
}

Posted by Microsoft on 2/3/2011 at 11:27 PM

Thank you for reporting this issue. At this time, we do not have plans to address this issue

-Sean

Posted by Microsoft on 9/8/2010 at 5:02 PM

Thank you for your feedback, we are currently reviewing the issue you have submitted. If this issue is urgent, please contact support directly(http://support.microsoft.com)

Posted by Pablo1397 on 8/8/2012 at 3:43 AM

a better solution is:

    public void ClearPointsQuick()
        {
            Points.SuspendUpdates();
            while (Points.Count > 0)
                Points.RemoveAt(Points.Count - 1);
            Points.ResumeUpdates();
            Points.Clear();
        }

Posted by selfcomposed on 9/8/2010 at 12:43 PM

    public void ClearPointsQuick()
        {
            Points.SuspendUpdates();
            while (Points.Count > 0)
                Points.RemoveAt(Points.Count - 1);
            Points.ResumeUpdates();
        }