Drawing 类 (System.Windows.Media)

.NET Framework 类库

Drawing 类

更新：2007 年 11 月

描述二维绘图的抽象类。此类不能由您的代码继承。

命名空间： System.Windows.Media
程序集： PresentationCore（在 PresentationCore.dll 中）

语法

Visual Basic（声明）

<LocalizabilityAttribute(LocalizationCategory.None, Readability := Readability.Unreadable)> _
Public MustInherit Class Drawing _
    Inherits Animatable

Visual Basic (用法)

Dim instance As Drawing

[LocalizabilityAttribute(LocalizationCategory.None, Readability = Readability.Unreadable)]
public abstract class Drawing : Animatable

Visual C++

[LocalizabilityAttribute(LocalizationCategory::None, Readability = Readability::Unreadable)]
public ref class Drawing abstract : public Animatable

/** @attribute LocalizabilityAttribute(LocalizationCategory.None, Readability = Readability.Unreadable) */
public abstract class Drawing extends Animatable

JScript

public abstract class Drawing extends Animatable

XAML

该类为抽象类；有关 XAML 中可用的派生的非抽象类，请参见 继承层次结构。

备注

Drawing 对象是轻量对象，允许您将几何形状、图像、文本和媒体添加到应用程序中。Drawing 对象被视为轻量对象，因为它们不提供对布局系统、输入概述和焦点的支持。因为这些对象具有性能优势，所以绘图是背景和剪贴画的理想选择。当在 Visual 级别编程时，也可使用绘图。

由于它们继承自 Freezable 类，因此 Drawing 对象可提供其他功能来使它们可用于描述剪贴画和背景：它们可按资源中的方式进行声明、在多个对象之间共享、设为只读以及设为线程安全。有关 Freezable 对象提供的不同功能的更多信息，请参见 Freezable 对象概述。

有不同类型的 Drawing 对象可用于不同类型的内容：GeometryDrawing、ImageDrawing、DrawingGroup、VideoDrawing 和 GlyphRunDrawing。

Freezable 功能

Drawing 是一种 Freezable 对象。有关 Freezable 功能（例如冻结和克隆）的信息，请参见 Freezable 对象概述。

示例

本示例演示如何使用 Drawing 绘制一个区域。若要使用 Drawing 绘制区域，应使用一个 DrawingBrush 以及一个或多个 Drawing 对象。下面的示例使用 DrawingBrush 绘制一个具有由两个椭圆组成的 Drawing 的对象。

XAML

<!-- Demonstrates the use of DrawingBrush. -->
<Page  
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  Background="White">
  <StackPanel Margin="20">

    <Rectangle Width="150" Height="150" Stroke="Black" StrokeThickness="1">
      <Rectangle.Fill>
        <DrawingBrush>
          <DrawingBrush.Drawing>
            <GeometryDrawing Brush="MediumBlue">
              <GeometryDrawing.Geometry>
                <GeometryGroup>
                  <EllipseGeometry RadiusX="20" RadiusY="45" Center="50,50" />
                  <EllipseGeometry RadiusX="45" RadiusY="20" Center="50,50" />
                </GeometryGroup>
              </GeometryDrawing.Geometry>
              <GeometryDrawing.Pen>
                <Pen Thickness="10">
                  <Pen.Brush>
                    <LinearGradientBrush>
                      <GradientStop Offset="0.0" Color="Black" />
                      <GradientStop Offset="1.0" Color="Gray" />
                    </LinearGradientBrush>
                  </Pen.Brush>
                </Pen>
              </GeometryDrawing.Pen>
            </GeometryDrawing>
          </DrawingBrush.Drawing>
        </DrawingBrush>
      </Rectangle.Fill>
    </Rectangle>
  </StackPanel>
</Page>

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;


namespace Microsoft.Samples.DrawingBrushExamples
{
    /// <summary>
    /// Paints a Rectangle element with a DrawingBrush.
    /// </summary>
    public class DrawingBrushExample : Page
    {
        public DrawingBrushExample()
        {
            Background = Brushes.White;
            StackPanel mainPanel = new StackPanel();

            // Create a drawing of two ellipses.
            GeometryDrawing aDrawing = new GeometryDrawing();

            // Use geometries to describe two overlapping ellipses.
            EllipseGeometry ellipse1 = new EllipseGeometry();
            ellipse1.RadiusX = 20;
            ellipse1.RadiusY = 45;
            ellipse1.Center = new Point(50, 50);
            EllipseGeometry ellipse2 = new EllipseGeometry();
            ellipse2.RadiusX = 45;
            ellipse2.RadiusY = 20;
            ellipse2.Center = new Point(50, 50);
            GeometryGroup ellipses = new GeometryGroup();
            ellipses.Children.Add(ellipse1);
            ellipses.Children.Add(ellipse2);

            // Add the geometry to the drawing.
            aDrawing.Geometry = ellipses;

            // Specify the drawing's fill.
            aDrawing.Brush = Brushes.Blue;

            // Specify the drawing's stroke.
            Pen stroke = new Pen();
            stroke.Thickness = 10.0;
            stroke.Brush = new LinearGradientBrush(
                Colors.Black, Colors.Gray, new Point(0, 0), new Point(1, 1));
            aDrawing.Pen = stroke;

            // Create a DrawingBrush
            DrawingBrush myDrawingBrush = new DrawingBrush();
            myDrawingBrush.Drawing = aDrawing;

            // Create a Rectangle element.
            Rectangle aRectangle = new Rectangle();
            aRectangle.Width = 150;
            aRectangle.Height = 150;
            aRectangle.Stroke = Brushes.Black;
            aRectangle.StrokeThickness = 1.0;

            // Use the DrawingBrush to paint the rectangle's
            // background.
            aRectangle.Fill = myDrawingBrush;

            mainPanel.Children.Add(aRectangle);

            this.Content = mainPanel;

        }
    }
}

下图显示该示例的输出。

（形状的中心是白色的，原因如如何：控制复合形状的填充中所述。）

通过设置 DrawingBrush 对象的 Viewport 和 TileMode 属性，可以创建重复模式。下面的示例使用基于由两个椭圆组成的 Drawing 创建的模式绘制一个对象。

XAML

<!-- Demonstrates the use of DrawingBrush. -->
<Page  
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  Background="White">
  <StackPanel Margin="20">

    <Rectangle Width="150" Height="150" Stroke="Black" StrokeThickness="1">
      <Rectangle.Fill>
        <DrawingBrush Viewport="0,0,0.25,0.25" TileMode="Tile">
          <DrawingBrush.Drawing>
            <GeometryDrawing Brush="MediumBlue">
              <GeometryDrawing.Geometry>
                <GeometryGroup>
                  <EllipseGeometry RadiusX="20" RadiusY="45" Center="50,50" />
                  <EllipseGeometry RadiusX="45" RadiusY="20" Center="50,50" />
                </GeometryGroup>
              </GeometryDrawing.Geometry>
              <GeometryDrawing.Pen>
                <Pen Thickness="10">
                  <Pen.Brush>
                    <LinearGradientBrush>
                      <GradientStop Offset="0.0" Color="Black" />
                      <GradientStop Offset="1.0" Color="Gray" />
                    </LinearGradientBrush>
                  </Pen.Brush>
                </Pen>
              </GeometryDrawing.Pen>
            </GeometryDrawing>
          </DrawingBrush.Drawing>
        </DrawingBrush>
      </Rectangle.Fill>
    </Rectangle>
  </StackPanel>
</Page>

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;


namespace Microsoft.Samples.DrawingBrushExamples
{

    /// <summary>
    /// Paints a Rectangle element with a tiled DrawingBrush.
    /// </summary>
    public class TiledDrawingBrushExample : Page
    {

        public TiledDrawingBrushExample()
        {
            Background = Brushes.White;
            StackPanel mainPanel = new StackPanel();

            // Create a drawing of two ellipses.
            GeometryDrawing aDrawing = new GeometryDrawing();

            // Use geometries to describe two overlapping ellipses.
            EllipseGeometry ellipse1 = new EllipseGeometry();
            ellipse1.RadiusX = 20;
            ellipse1.RadiusY = 45;
            ellipse1.Center = new Point(50, 50);
            EllipseGeometry ellipse2 = new EllipseGeometry();
            ellipse2.RadiusX = 45;
            ellipse2.RadiusY = 20;
            ellipse2.Center = new Point(50, 50);
            GeometryGroup ellipses = new GeometryGroup();
            ellipses.Children.Add(ellipse1);
            ellipses.Children.Add(ellipse2);

            // Add the geometry to the drawing.
            aDrawing.Geometry = ellipses;

            // Specify the drawing's fill.
            aDrawing.Brush = Brushes.Blue;

            // Specify the drawing's stroke.
            Pen stroke = new Pen();
            stroke.Thickness = 10.0;
            stroke.Brush = new LinearGradientBrush(
                Colors.Black, Colors.Gray, new Point(0, 0), new Point(1, 1));
            aDrawing.Pen = stroke;

            // Create a DrawingBrush
            DrawingBrush myDrawingBrush = new DrawingBrush();
            myDrawingBrush.Drawing = aDrawing;

            // Set the DrawingBrush's Viewport and TileMode
            // properties so that it generates a pattern.
            myDrawingBrush.Viewport = new Rect(0, 0, 0.25, 0.25);
            myDrawingBrush.TileMode = TileMode.Tile;

            // Create a Rectangle element.
            Rectangle aRectangle = new Rectangle();
            aRectangle.Width = 150;
            aRectangle.Height = 150;
            aRectangle.Stroke = Brushes.Black;
            aRectangle.StrokeThickness = 1.0;

            // Use the DrawingBrush to paint the rectangle's
            // background.
            aRectangle.Fill = myDrawingBrush;

            mainPanel.Children.Add(aRectangle);

            this.Content = mainPanel;

        }

    }
}