在DrawingContext中绘制一个填充三角形

这是这个问题的后续行动。

题：

我试图使用DrawingContext绘制一个填充三角形，它在DrawingVisual渲染

目前，我已设法使用以下C＃代码绘制三角形的轮廓：

 private DrawingVisual CreateTriangle() { DrawingVisual triangle = new DrawingVisual(); using ( DrawingContext dc = triangle.RenderOpen() ) { Pen drawingPen = new Pen(Brushes.Black,3); dc.DrawLine(drawingPen, new Point(0, 50), new Point(50, 0)); dc.DrawLine(drawingPen, new Point(50, 0), new Point(50, 100)); dc.DrawLine(drawingPen, new Point(50, 100), new Point(0, 50)); } return triangle; } 

我明白了：

如何绘制一个三角形，除了我绘制的边框还有红色填充？

Answer 1

使用dc.DrawGeometry创建填充形状。

编辑：这个：

 private DrawingVisual CreateTriangle() { var triangle = new DrawingVisual(); using (DrawingContext dc = triangle.RenderOpen()) { var start = new Point(0, 50); var segments = new [] { new LineSegment(new Point(50,0), true), new LineSegment(new Point(50, 100), true) }; var figure = new PathFigure(start, segments, true); var geo = new PathGeometry(new [] { figure }); dc.DrawGeometry(Brushes.Red, null, geo); var drawingPen = new Pen(Brushes.Black, 3); dc.DrawLine(drawingPen, new Point(0, 50), new Point(50, 0)); dc.DrawLine(drawingPen, new Point(50, 0), new Point(50, 100)); dc.DrawLine(drawingPen, new Point(50, 100), new Point(0, 50)); } return triangle; } 

另外，如果您必须创建PathGeometry并使用DrawGeometry您也可以使用它，然后您不需要原始线条图。

 dc.DrawGeometry(Brushes.Red, new Pen(Brushes.Black, 3), geo); 

Answer 2

也许有点旧，但它可能会帮助别人。 它不使用PathGeometry，而是使用Stream几何。 “ 这种几何形状是PathGeometry的轻量级替代品 ”

 Point p1 = new Point(0, 50); Point p2 = new Point(50, 0); Point p3 = new Point(50, 100); StreamGeometry streamGeometry = new StreamGeometry(); using (StreamGeometryContext geometryContext = streamGeometry.Open()) { geometryContext.BeginFigure(p1, true, true); PointCollection points = new PointCollection{ p2, p3 }; geometryContext.PolyLineTo(points, true, true); } streamGeometry.Freeze(); context.DrawGeometry(Brushes.Red, new Pen(Brushes.Black,3), streamGeometry); 

有关StreamGeometry的更多信息，请访问： https ：//msdn.microsoft.com/en-us/library/system.windows.media.streamgeometry.aspx

问候。