[WPF] 可选择的TextBlock，正则匹配高亮显示

　　实现TextBlock控件像TextBox一样支持选择文本，又保留TextBlock显示省略号等特性，找不到参考文献了，抱歉。

　　下面演示基于可选择TextBlock实现的效果：

 代码已上传至https://gitee.com/Pumbaa_Peng/textbook-demo.git。

<pp:ChromeWindow x:Class="TextBlockDemo.MainWindow"
                 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                 xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
                 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                 xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
                 xmlns:pp="https://www.cnblogs.com/pumbaa"
                 xmlns:behaviors="clr-namespace:TextBlockDemo.Behaviors"
                 xmlns:attach="clr-namespace:TextBlockDemo.Controls.Attach"
                 xmlns:i="http://schemas.microsoft.com/xaml/behaviors"
                 mc:Ignorable="d"
                 Title="MainWindow" Height="720" Width="1024"
                 UseLayoutRounding="True" SnapsToDevicePixels="True"
                 Background="{DynamicResource PP.Brushes.Background}" Foreground="{DynamicResource PP.Brushes.Foreground}" FontSize="16" TextBlock.LineHeight="24">
    <pp:ScrollViewerEx HorizontalScrollBarVisibility="Disabled">
        <StackPanel Margin="18">
            <TextBlock FontSize="18" LineHeight="36">示例一</TextBlock>
            <TextBlock Style="{StaticResource App.Styles.TextBlock.Selectable}" Foreground="{DynamicResource PP.Brushes.Warning.Highlight}">这是普通的可选TextBlock</TextBlock>
            <Line X2="1" Stretch="Uniform" Stroke="#999" Margin="0 18"></Line>
            <TextBlock FontSize="18" LineHeight="36">示例二</TextBlock>
            <TextBlock Foreground="{DynamicResource PP.Brushes.Warning.Highlight}" LineHeight="24">可选择文本超出时显示省略号，选择时隐藏省略号</TextBlock>
            <DockPanel Margin="0 12">
                <TextBlock Foreground="#666" VerticalAlignment="Center">绑定文本：</TextBlock>
                <TextBox x:Name="input" MinWidth="400" TextWrapping="Wrap" VerticalContentAlignment="Top" Text="在WPF（Windows Presentation Foundation）中，文本修整是一种常用的技术，用于处理文本内容超出其显示区域时的情况。通过设置TextBlock的TextTrimming属性，可以指定当文本超出其容器边界时应如何显示。这个属性接受TextTrimming枚举的值，这些值决定了文本的修整行为。" />
            </DockPanel>
            <TextBox Style="{StaticResource App.Styles.TextBox.SelectableTextBlock}" MaxWidth="400" HorizontalAlignment="Left" Text="{Binding Text,ElementName=input}" />
            <Line X2="1" Stretch="Uniform" Stroke="#999" Margin="0 18"></Line>
            <TextBlock FontSize="18" LineHeight="36">示例三</TextBlock>
            <TextBlock Foreground="{DynamicResource PP.Brushes.Warning.Highlight}" LineHeight="24">多行可选择文本超出时显示省略号，选择时隐藏省略号</TextBlock>
            <DockPanel Margin="0 12">
                <TextBlock Foreground="#666" VerticalAlignment="Center">行数：</TextBlock>
                <Slider x:Name="slider" Minimum="1" Maximum="10" Value="3" SmallChange="1" Width="400" HorizontalAlignment="Left"
                        TickFrequency="1" TickPlacement="BottomRight" IsSnapToTickEnabled="True" />
            </DockPanel>
            <TextBox Style="{StaticResource App.Styles.TextBox.SelectableTextBlock.MaxLines}" MaxLines="{Binding Value,ElementName=slider}" MaxWidth="400" HorizontalAlignment="Left" Text="{Binding Text,ElementName=input}" />
            <Line X2="1" Stretch="Uniform" Stroke="#999" Margin="0 18"></Line>
            <TextBlock FontSize="18" LineHeight="36">示例四</TextBlock>
            <TextBlock Foreground="{DynamicResource PP.Brushes.Warning.Highlight}" LineHeight="24">多行可选择文本超出时显示省略号，选择时隐藏展开</TextBlock>
            <TextBox Style="{StaticResource App.Styles.TextBox.SelectableTextBlock.AutoExpand}" MaxLines="{Binding Value,ElementName=slider}" Margin="0 12 0 0" MaxWidth="400" HorizontalAlignment="Left" Text="{Binding Text,ElementName=input}" />
            <Line X2="1" Stretch="Uniform" Stroke="#999" Margin="0 18"></Line>
            <TextBlock FontSize="18" LineHeight="36">示例五</TextBlock>
            <TextBlock Foreground="{DynamicResource PP.Brushes.Warning.Highlight}" LineHeight="24">文本正则高亮显示（可以多个正则，每个正则不同颜色）</TextBlock>
            <TextBlock Margin="0 12 0 0" Style="{StaticResource App.Styles.TextBlock.Selectable}" TextWrapping="Wrap" attach:TextElement.Placeholder="{Binding Text,ElementName=input}">
                <i:Interaction.Behaviors>
                    <behaviors:TextHighlightBehavior>
                        <behaviors:TextHighlightBehavior.HighlightRules>
                            <behaviors:HighlightRule Regex="[a-zA-Z]+" Brush="#F5201B" />
                            <behaviors:HighlightRule Regex="文本|技术" Brush="#F69A18" />
                        </behaviors:TextHighlightBehavior.HighlightRules>
                    </behaviors:TextHighlightBehavior>
                </i:Interaction.Behaviors>
            </TextBlock>
            <Line X2="1" Stretch="Uniform" Stroke="#999" Margin="0 18"></Line>
        </StackPanel>
    </pp:ScrollViewerEx>
</pp:ChromeWindow>