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，而且绘制错误。 但是，我在DrawingContext类中搜索了一种绘制圆弧的方法，但没有找到。

            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

您必须绘制一个包含圆弧段的PathGeometry 或StreamGeometry，如下面的半径为 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);
}