如何在c# WPF中使用参数绘制圆弧?

Question

我想知道如何在c#中绘制弧线，我正在尝试使用DrawEllipse，但它不起作用，它给出了错误的绘图。然而，我已经寻找了一种方法来绘制类DrawingContext中的弧，但我没有找到它。

DrawingVisual d = new DrawingVisual();
System.Windows.Media.Pen pen = new System.Windows.Media.Pen();
DrawingContext drawingContext = d.RenderOpen();
pen.Brush = System.Windows.Media.Brushes.Black;
System.Windows.Point center = new System.Windows.Point();
center.X = 0.4;
center.Y = 0.5;
drawingContext.DrawEllipse(System.Windows.Media.Brushes.White, pen, center, 4,4);
drawingContext.Close();
canvas.Children.Add(new VisualHost { Visual = d });

Answer 1

您必须绘制包含弧段的PathGeometry或StreamGeometry，如以下半径为100的圆弧，从(100,100)到(200,200):

var visual = new DrawingVisual();
var pen = new Pen(Brushes.Black, 1);
using (var dc = visual.RenderOpen())
{
var figure = new PathFigure
{
StartPoint = new Point(100, 100) // start point
};
figure.Segments.Add(new ArcSegment
{
Point = new Point(200, 200), // end point
Size = new Size(100, 100),   // radii
SweepDirection = SweepDirection.Clockwise
});
var geometry = new PathGeometry();
geometry.Figures.Add(figure);
dc.DrawGeometry(null, pen, geometry);
}