c# - 在 DrawingContext 中绘制一个实心三角形

Question

这是此 question 的跟进.

问题:

我正在尝试使用 DrawingContext 绘制一个实心三角形，它在 DrawingVisual 上呈现

目前，我已经成功地使用以下 C# 代码绘制了三角形的轮廓:

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:

我如何绘制一个三角形，除了我绘制的边框外还有一个红色填充？

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;
}

附带说明一下，如果您无论如何都必须创建 PathGeometry 并且您使用了 DrawGeometry，那么您也可以对它进行描边，那么您就不需要原始的线条图。

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