c# - 如何在 Windows Phone 中动态绘制扇区(四分之一圆)？

Question

我想绘制图像中的形状。 我已经用Arc Segment画了半个圆，现在我想画四分之一圆，或者一个扇形，但是我画不出来。

我用这段代码画弧形，我试着改变大小，角度也不行。

我应该怎么做才能绘制四分之一圆圈/扇区？？我用来绘制 Arc 的代码是:

PathFigure pthFigure1 = new PathFigure();
pthFigure1.StartPoint = new Point(50, 60);// starting cordinates of arcs
ArcSegment arcSeg1 = new ArcSegment();
arcSeg1.Point = new Point(100, 82);   // ending cordinates of arcs
arcSeg1.Size = new Size(10, 10);

arcSeg1.IsLargeArc = false;
arcSeg1.SweepDirection = SweepDirection.Clockwise;
arcSeg1.RotationAngle = 90;
PathSegmentCollection myPathSegmentCollection1 = new PathSegmentCollection();
myPathSegmentCollection1.Add(arcSeg1);
pthFigure1.Segments = myPathSegmentCollection1;
PathFigureCollection pthFigureCollection1 = new PathFigureCollection();
pthFigureCollection1.Add(pthFigure1);
PathGeometry pthGeometry1 = new PathGeometry();
pthGeometry1.Figures = pthFigureCollection1;
System.Windows.Shapes.Path arcPath1 = new System.Windows.Shapes.Path();
arcPath1.Data = pthGeometry1;
arcPath1.Fill = new SolidColorBrush(Color.FromArgb(255, 255, 23, 0));
this.LayoutRoot.Children.Add(arcPath1);

Answer 1

对您的代码进行最少的更改(/**/ 表示更改或添加的行)。

PathFigure pthFigure1 = new PathFigure();
/**/ pthFigure1.StartPoint = new Point(0, 100);// starting cordinates of arcs
ArcSegment arcSeg1 = new ArcSegment();
/**/ arcSeg1.Point = new Point(100, 0);   // ending cordinates of arcs
/**/ arcSeg1.Size = new Size(100, 100);
arcSeg1.IsLargeArc = false;
arcSeg1.SweepDirection = SweepDirection.Clockwise;
/**/ LineSegment lineSeg = new LineSegment();
/**/ lineSeg.Point = new Point(100,100);
PathSegmentCollection myPathSegmentCollection1 = new PathSegmentCollection();
myPathSegmentCollection1.Add(arcSeg1);
/**/ myPathSegmentCollection1.Add(lineSeg);
pthFigure1.Segments = myPathSegmentCollection1;
PathFigureCollection pthFigureCollection1 = new PathFigureCollection();
pthFigureCollection1.Add(pthFigure1);
...

您似乎误解了 ArcSegment.RotationAngle 的含义。

它的数学原理: