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RegisterName throws NullReferenceException

Posted By:      Posted Date: September 09, 2010    Points: 0   Category :WPF
Hi I am having a problem registering a controls name, so that I can remove the control when I need to redraw it. when trying to register the name it throws a NullReferenceException, can anyone see a problem with the code? private void DrawSegment(Point p1, Point p2, Point p3, Point p4, bool reflexangle, Color clr) { // Segment Geometry PathSegmentCollection segments = new PathSegmentCollection(); // First line segment from pt p1 - pt p2 segments.Add(new LineSegment() { Point = p2 }); //Arc drawn from pt p2 - pt p3 with the RangeIndicatorRadius segments.Add(new ArcSegment() { Size = new Size(arcradius2, arcradius2), Point = p3, SweepDirection = SweepDirection.Clockwise, IsLargeArc = reflexangle }); // Second line segment from pt p3 - pt p4 segments.Add(new LineSegment() { Point = p4 }); //Arc drawn from pt p4 - pt p1 with the Radius of arcradius1 segments.Add(new ArcSegment() { Size = new Size(arcradius1, arcradius1), Point = p1, SweepDirection = SweepDirection.Counterclockwise, IsLargeArc = reflexangle }); // Defining the segment path properties Color rangestrokecolor; if (clr == Colors.Transparent) { rangestrokecolor = clr; } else rangestrokecolor = Colors.White;

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