c# - TextHighlighter RichTextBlock UWP

Question

我想用 TextHighlighter 对象突出显示 richtextblock 的一些文本。我创建了一个 TextRange，将其添加到列表中，然后创建了一个新的 TextHighlighter 实例并设置了背景颜色。但是现在我不能使用 TextHighlighter 来突出显示文本。我应该如何进行？

xaml:

 <Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
    <StackPanel HorizontalAlignment="Center" VerticalAlignment="Center" Width="300">
        <RichTextBlock x:Name="RichFullText" Margin="0,0,0,10">
            <Paragraph x:Name="Testo">
                <Run Foreground="Blue" FontSize="24" FontStyle="Italic">
                    This is a
                </Run>
                <Run Foreground="Teal" FontFamily="Segoe UI Light" FontSize="18" >
                    example text
                </Run>
                <Run Foreground="Black" FontFamily="Arial" FontSize="14" FontWeight="Bold">
                    format
                </Run>
            </Paragraph>
        </RichTextBlock>
        <Grid HorizontalAlignment="Stretch" VerticalAlignment="Bottom">
            <TextBox x:Name="txbToFind" Height="32" VerticalAlignment="Bottom" Width="200" HorizontalAlignment="Left"/>
            <Button x:Name="btnToFind" Content="Find" Click="btnToFind_Click" HorizontalAlignment="Right" VerticalAlignment="Center"/>
        </Grid>
    </StackPanel>
</Grid>

xaml.cs:

public sealed partial class MainPage : Page
{
    public MainPage()
    {
        this.InitializeComponent();
    }

    private void btnToFind_Click(object sender, RoutedEventArgs e)
    {
        TextRange textRange = new TextRange() { StartIndex = 3, Length = 5 };
        List<TextRange> rangelist = new List<TextRange>();
        rangelist.Add(textRange);
        TextHighlighter evidenziatore = new TextHighlighter() { Background = new SolidColorBrush(Colors.Yellow) };
        //RichFullText... There I would apply highlight to RichTextBlock
    }
}

如何使用 TextHighlighter 突出显示？

Answer 1

您需要将 TextHighlighter 添加到 RichTextBlock 的 TextHighlighters 集合中:

TextRange textRange = new TextRange() { StartIndex = 3, Length = 10 };            
TextHighlighter highlighter = new TextHighlighter()
{
    Background = new SolidColorBrush(Colors.Yellow),
    Ranges = { textRange }
};
//add the highlighter
RichBlock.TextHighlighters.Add(highlighter);

另请注意，我已将 textRange 添加到您的 TextHighlighter 实例中的 Ranges 集合中。