如何将缓存元素用作画笔
使用 BitmapCacheBrush 类高效重用缓存元素。 若要缓存元素，请创建 BitmapCache 类的新实例，并将其分配给元素的 CacheMode 属性。
例
下面的代码示例演示如何重复使用缓存的元素。 缓存元素是显示大型图像的 Image 控件。 Image 控件被 BitmapCache 类缓存为位图，并通过将缓存分配给 BitmapCacheBrush来重新使用。 将画笔分配到二十五个按钮的背景中，以展示高效的重用。
<Window x:Class="BitmapCacheBrushDemo.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
Height="300" Width="300" >
<Window.Resources>
<RichTextBox x:Key="cachedRichTextBox" >
<RichTextBox.CacheMode>
<BitmapCache EnableClearType="True" RenderAtScale="1" SnapsToDevicePixels="True" />
</RichTextBox.CacheMode>
</RichTextBox>
<BitmapCacheBrush x:Key="cachedRichTextBoxBrush" Target="{StaticResource cachedRichTextBox}">
<BitmapCacheBrush.BitmapCache>
<BitmapCache EnableClearType="False" RenderAtScale="0.4" SnapsToDevicePixels="False" />
</BitmapCacheBrush.BitmapCache>
</BitmapCacheBrush>
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="*" />
<ColumnDefinition Width="*" />
<ColumnDefinition Width="*" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Name="button1" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Name="button2" Grid.Column="1" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Name="button3" Grid.Column="2" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Name="button4" Grid.Column="3" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Name="button5" Grid.Column="4" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Name="button6" Grid.Row="1" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="1" Name="button7" Grid.Row="1" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="2" Name="button8" Grid.Row="1" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="3" Name="button9" Grid.Row="1" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="4" Name="button10" Grid.Row="1" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Name="button11" Grid.Row="2" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="1" Name="button12" Grid.Row="2" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="2" Name="button13" Grid.Row="2" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="3" Name="button14" Grid.Row="2" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="4" Name="button15" Grid.Row="2" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Name="button16" Grid.Row="3" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="1" Name="button17" Grid.Row="3" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="2" Name="button18" Grid.Row="3" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="3" Name="button19" Grid.Row="3" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="4" Name="button20" Grid.Row="3" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Name="button21" Grid.Row="4" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="1" Name="button22" Grid.Row="4" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="2" Name="button23" Grid.Row="4" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="3" Name="button24" Grid.Row="4" FontWeight="Bold" />
<Button Background="{StaticResource cachedRichTextBoxBrush}" Content="Button" Grid.Column="4" Name="button25" Grid.Row="4" FontWeight="Bold" />
</Grid>
</Window>
