画刷（3）

五 使用绘图绘制
DrawingBrush使用绘制区域 Drawing 。 Drawing可以包含形状、图像、文本和媒体。 下面的示例使用 DrawingBrush 绘制 Fill 的 Rectangle 。
使用 System.windows.media.drawingbrush> 绘制的矩形
C#：

using System.Windows;
using System.Windows.Media;
using System.Windows.Shapes;
namespace WpfApplication
{
    /// 

    /// Window1.xaml 的交互逻辑
    /// 
    public partial class Window1 : Window
    {
        public Window1()
        {
            InitializeComponent();
        }
        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            //实例化矩形并设置宽度和高度
            Rectangle exampleRectangle = new Rectangle();
            exampleRectangle.Width = 75;
            exampleRectangle.Height = 75;
            // 创建一个DrawingBrush并使用它 
            DrawingBrush myBrush = new DrawingBrush();
            // （1）绘制
            /*
            参数:
            brush:
            用于填充此 System.Windows.Media.GeometryDrawing 的画笔。
            pen:
            用于绘制此 System.Windows.Media.GeometryDrawing 的钢笔。
             geometry:
             几何图形
             */
            GeometryDrawing backgroundSquare =
            new GeometryDrawing(
            Brushes.White,
            null,
            new RectangleGeometry(new Rect(0, 0, 100, 100)));
            //复合几何图形
            GeometryGroup aGeometryGroup = new GeometryGroup();
            aGeometryGroup.Children.Add(new RectangleGeometry(new
           Rect(0, 0, 50, 50)));
            aGeometryGroup.Children.Add(new RectangleGeometry(new
           Rect(50, 50, 50, 50)));
            //使用线性渐变绘制区域
            LinearGradientBrush checkerBrush = new
           LinearGradientBrush();
            checkerBrush.GradientStops.Add(new
           GradientStop(Colors.Black, 0.0));
            checkerBrush.GradientStops.Add(new
           GradientStop(Colors.Gray, 1.0));
            // （2）绘制
            GeometryDrawing checkers = new
           GeometryDrawing(checkerBrush, null, aGeometryGroup);
            //绘图集合：把（1）绘制和（2）绘制添加到集合里面
            DrawingGroup checkersDrawingGroup = new DrawingGroup();
            checkersDrawingGroup.Children.Add(backgroundSquare);
            checkersDrawingGroup.Children.Add(checkers);
            myBrush.Drawing = checkersDrawingGroup;
            myBrush.Viewport = new Rect(0, 0, 0.25, 0.25);
            myBrush.TileMode = TileMode.Tile;
            //设置填充
            exampleRectangle.Fill = myBrush;
            //把矩形添加到GD_Main里面
            GD_Main.Children.Add(exampleRectangle);
        }
    }
}

XAML：

<Rectangle Width="75" Height="75">
    <Rectangle.Fill>
        <DrawingBrush Viewport="0,0,0.25,0.25" TileMode="Tile">
            <DrawingBrush.Drawing>
                <DrawingGroup>
                    <GeometryDrawing Brush="White">
                        <GeometryDrawing.Geometry>
                            <RectangleGeometry Rect="0,0,100,100" />
                        GeometryDrawing.Geometry>
                    GeometryDrawing>
                    <GeometryDrawing>
                        <GeometryDrawing.Geometry>
                            <GeometryGroup>
                                <RectangleGeometry Rect="0,0,50,50" />
                                <RectangleGeometry Rect="50,50,50,50" />
                            GeometryGroup>
                        GeometryDrawing.Geometry>
                        <GeometryDrawing.Brush>
                            <LinearGradientBrush>
                                <GradientStop Offset="0.0" Color="Black" />
                                <GradientStop Offset="1.0" Color="Gray" />
                            LinearGradientBrush>
                        GeometryDrawing.Brush>
                    GeometryDrawing>
                DrawingGroup>
            DrawingBrush.Drawing>
        DrawingBrush>
    Rectangle.Fill>
Rectangle>

效果图：