FlowDocumentPageViewer 搜索文本和突出显示

Question

我正在使用 FlowDocumentPageViewer 创建搜索并突出显示文本，类似于给定的链接。

http://kentb.blogspot.com/ 2009/06/search-and-highlight-text-in-任意.html

当我搜索字符串标记时，（使用字符串列表）一切正常，并且我得到了适当应用的矩形。但我这里有两个问题，

1. 当我更改FlowDocumentPageViewer的页面时，我的矩形突出显示区域保持不变，并且没有随文本下沉。

2. 当我放大或缩小 FlowDocumentPageViewer 时，文本会缩放，但突出显示矩形仍保持在相同位置，

您能否帮助我解决此问题，以便将矩形应用于文本本身。我在这里提出我的申请。如果您需要更多信息，请仍然告诉我。

    <StackPanel Grid.Row="0" Orientation="Horizontal">
        <TextBox x:Name="_searchTextBox" Text="{Binding SearchText, UpdateSourceTrigger=PropertyChanged}" Width="200" Height="20" Margin="2"/>
        <Button x:Name="_searchButton" Height="{Binding Height, ElementName=_searchTextBox}" Width="50" Content="GO">
            </Button>
            <Button x:Name="_listItems" Height="{Binding Height, ElementName=_searchTextBox}" Width="50" Content="List"/>
        </StackPanel>

    <Grid Grid.Row="1">
        <FlowDocumentPageViewer>
            <FlowDocument Foreground="Black" FontFamily="Arial">
                <Paragraph FontSize="11">
                    The following details have been details from Amazon to match your initial query.Some of the returned values may have been empty, so have been ommitted from theresults shown here.Also where there have been more than one value returned viathe Amazon Details, these to have beenomitted for the sake of keeping things simplefor this small demo application. Simple is good,when trying to show how something works
                </Paragraph>
            </FlowDocument>
        </FlowDocumentPageViewer>
    </Grid>

    <ItemsControl ItemsSource="{Binding SearchRectangles}">
        <ItemsControl.ItemsPanel>
            <ItemsPanelTemplate>
                <Canvas/>
            </ItemsPanelTemplate>
        </ItemsControl.ItemsPanel>
        <ItemsControl.ItemTemplate>
            <DataTemplate>
                    <Rectangle Fill="#99FFFF00" Width="{Binding Width}"  Height="{Binding Height}"  Tag="{Binding Text}"  MouseDown="Rectangle_MouseDown">
                        <Rectangle.Style>
                            <Style TargetType="{x:Type Rectangle}">
                                <Style.Triggers>
                                    <Trigger Property="IsMouseOver" Value="True">
                                        <Setter Property="BitmapEffect">
                                            <Setter.Value>
                                                <OuterGlowBitmapEffect GlowColor="BurlyWood" GlowSize="7"/>
                                            </Setter.Value>
                                        </Setter>
                                    </Trigger>
                                </Style.Triggers>
                            </Style>
                        </Rectangle.Style>

                    </Rectangle>
                </DataTemplate>
        </ItemsControl.ItemTemplate>
        <ItemsControl.ItemContainerStyle>
            <Style>
                <Setter Property="Canvas.Top" Value="{Binding Top}"/>
                <Setter Property="Canvas.Left" Value="{Binding Left}"/>
            </Style>
        </ItemsControl.ItemContainerStyle>
    </ItemsControl>

</Grid>
</Grid>

public partial class Window1 : Window
{
    public static readonly DependencyProperty SearchTextProperty = DependencyProperty.Register("SearchText",
                                            typeof(string),
                                            typeof(Window1));

    public static readonly DependencyProperty SearchRectanglesProperty = DependencyProperty.Register("SearchRectangles",
                    typeof(ICollection<SearchRectangle>),
                    typeof(Window1));



    public IList<string> SearchTokens { get; set; }


    public Window1()
    {
        InitializeComponent();

        SearchRectangles = new ObservableCollection<SearchRectangle>();

        _searchButton.Click += delegate
        {
            DoSearch();
        };

        _listItems.Click += delegate
        {
            SearchTokens = new List<string>();
            SearchTokens.Add("been");
            SearchTokens.Add("Amazon");
            SearchTokens.Add("following");              
            DoSearch(SearchTokens);

        };

        _searchTextBox.KeyDown += delegate(object sender, KeyEventArgs e)
        {
            if (e.Key == Key.Enter)
            {
                DoSearch();
            }
        };
    }


    public void DoSearch(IList<string> searchTokens)
    {

        SearchRectangles.Clear();

        if (searchTokens == null)
            return;

        foreach (string token in searchTokens)
        {
            SearchText = token;
            DoSearch();
        }
    }

    public string SearchText
    {
        get { return GetValue(SearchTextProperty) as string; }
        set { SetValue(SearchTextProperty, value); }
    }

    public ICollection<SearchRectangle> SearchRectangles
    {
        get { return GetValue(SearchRectanglesProperty) as ICollection<SearchRectangle>; }
        set { SetValue(SearchRectanglesProperty, value); }
    }

    private void DoSearch()
    {
        DoSearch(false);
    }

    private void DoSearch(bool clearExisting)
    {
        if( clearExisting == true ) 
            SearchRectangles.Clear();
        if (SearchText.Length == 0)
        {
            return;
        }

        DoSearch(this);
    }

    private void DoSearch(DependencyObject searchIn)
    {
        if (searchIn == null)
        {
            return;
        }

        var contentHost = searchIn as IContentHost;

        if (contentHost != null)
        {
            DoSearch(contentHost as UIElement, contentHost);
        }
        else
        {
            var documentViewerBase = searchIn as DocumentViewerBase;

            if (documentViewerBase != null)
            {
                //extract the content hosts from the document viewer
                foreach (var pageView in documentViewerBase.PageViews)
                {
                    contentHost = pageView.DocumentPage as IContentHost;

                    if (contentHost != null)
                    {
                        DoSearch(documentViewerBase, contentHost);
                    }
                }
            }
        }

        //recurse through children
        var childCount = VisualTreeHelper.GetChildrenCount(searchIn);

        for (var i = 0; i < childCount; ++i)
        {
            DoSearch(VisualTreeHelper.GetChild(searchIn, i));
        }
    }

    private void DoSearch(UIElement uiHost, IContentHost contentHost)
    {
        if (uiHost == null)
        {
            return;
        }

        var textBlock = contentHost as TextBlock;

        if (textBlock != null)
        {
            //this has the side affect of converting any plain string content in the TextBlock into a hosted Run element
            //that's bad in that it is unexpected, but good in that it allows us to access the hosted elements in a
            //consistent fashion below, rather than special-casing TextBlocks with text only content
            var contentStart = textBlock.ContentStart;
        }

        var hostedElements = contentHost.HostedElements;

        while (hostedElements.MoveNext())
        {
            var run = hostedElements.Current as Run;

            if (run != null && !string.IsNullOrEmpty(run.Text))
            {
                ApplyHighlighting(run.Text, delegate(int start, int length)
                {
                    var textPointer = run.ContentStart;
                    textPointer = textPointer.GetPositionAtOffset(start, LogicalDirection.Forward);
                    var leftRectangle = textPointer.GetCharacterRect(LogicalDirection.Forward);
                    textPointer = textPointer.GetPositionAtOffset(length, LogicalDirection.Forward);
                    var rightRectangle = textPointer.GetCharacterRect(LogicalDirection.Backward);
                    var rect = new Rect(leftRectangle.TopLeft, rightRectangle.BottomRight);
                    var translatedPoint = uiHost.TranslatePoint(new Point(0, 0), null);
                    rect.Offset(translatedPoint.X, translatedPoint.Y);
                    return rect;
                });

            }
        }
    }

    private void ApplyHighlighting(string text, Func<int, int, Rect> getRectHandler)
    {
        var currentIndex = 0;

        while (true)
        {
            var index = text.IndexOf(SearchText, currentIndex, StringComparison.CurrentCultureIgnoreCase);

            if (index == -1)
            {
                return;
            }

            var rect = getRectHandler(index, SearchText.Length);

            if (rect != Rect.Empty)
            {
                SearchRectangles.Add(new SearchRectangle(rect.Top, rect.Left, rect.Width, rect.Height,SearchText));
            }

            currentIndex = index + SearchText.Length;
        }
    }

    private void Rectangle_MouseDown(object sender, MouseEventArgs e)
    {
        Rectangle r = sender as Rectangle;
        MessageBox.Show(r.Tag.ToString());
    }

    private void FlowDocumentPageViewer_PageViewsChanged(object sender, EventArgs e)
    {

    }

    private void Window_SizeChanged(object sender, SizeChangedEventArgs e)
    {
        DoSearch(SearchTokens);
    }

}

public class SearchRectangle
{
    private readonly double _top;
    private readonly double _left;
    private readonly double _width;
    private readonly double _height;
    private readonly string _text;

    public SearchRectangle(double top, double left, double width, double height,string text)
    {
        _top = top;
        _left = left;
        _width = width;
        _height = height;
        _text = text;

    }

    public string Text
    {
        get { return _text; }
    }

    public double Top
    {
        get { return _top; }
    }

    public double Left
    {
        get { return _left; }
    }

    public double Width
    {
        get { return _width; }
    }

    public double Height
    {
        get { return _height; }
    }
}

最好的，

巴拉。

Answer 1

看似简单的解决方案是实际编辑文档以在搜索时进行突出显示，并记住在清除搜索结果或需要未编辑的文档用于其他目的（例如保存它）时将其编辑回来。

您可以使用 我在此答案中发布的代码。在您的情况下，您不需要将选择设置为找到的每个范围，而是需要像这样突出显示该范围：

public void HilightMatches(TextRange searchRange, string searchText)
{
  var start = searchRange.Start;
  while(start != searchRange.End)
  {
    var foundRange = FindTextInRange(
      new TextRange(start, searchRange.End),
      searchText);

    if(foundRange==null) return;
    // Here is the meat...
    foundRange.ApplyPropertyValue(TextElement.BackgroundProperty, Brushes.Yellow);
    start = foundRange.End;
  }
}

要完成图片，您需要一种在完成后清除突出显示的方法。几个选项：

1. 保存突出显示的范围，以便您可以仅使用ApplyPropertyValue来应用画笔。透明背景（简单，但这将删除以前设置的任何背景）

2. 将找到的每个范围拆分为运行并保存每个运行列表及其原始背景颜色，因此它将很容易恢复

3. 在修改之前保存整个文档，然后只需恢复它即可删除高亮显示

4. 如果文档位于 RichTextBox 中并且不允许用户编辑该文档，您可以简单地使用撤消机制。确保在进行高亮显示时增加 TextBoxBase.UndoLimit，然后要删除高亮显示，只需为每个高亮调用一次 TextBoxBase.Undo() 即可。

Answer 2

尝试这个解决方案
http://rredcat.blogspot.com/ 2009/11/zoom-and-page-chahged-events-for.html