WPF TextBlock 根据搜索条件突出显示某些部分

WPF TextBlock 根据搜索条件突出显示某些部分

xaml
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="TextBlock Highlighting Example" Height="450" Width="800">
    
        
        
    

csharp
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Media;
namespace TextBlockHighlightingExample
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }
        private void searchTextBox_TextChanged(object sender, TextChangedEventArgs e)
        {
            string searchText = searchTextBox.Text;
            if (!string.IsNullOrEmpty(searchText))
            {
                string text = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed dapibus dolor at dui maximus, non luctus nisi ultricies. Mauris auctor orci non nunc iaculis, eu tempor mi convallis. Nulla facilisi. Sed at commodo magna. Vivamus suscipit commodo fermentum. Suspendisse non leo id metus tempor ultricies. Duis id ultrices ligula, at tristique metus. Nam vitae nisi nec nulla sagittis pellentesque.";
                textBlock.Inlines.Clear();
                int index = text.IndexOf(searchText);
                int lastIndex = 0;
                while (index != -1)
                {
                    textBlock.Inlines.Add(text.Substring(lastIndex, index - lastIndex));
                    Run highlightRun = new Run(text.Substring(index, searchText.Length));
                    highlightRun.Background = Brushes.Yellow;
                    textBlock.Inlines.Add(highlightRun);
                    lastIndex = index + searchText.Length;
                    index = text.IndexOf(searchText, lastIndex);
                }
                textBlock.Inlines.Add(text.Substring(lastIndex));
            }
            else
            {
                textBlock.Text = string.Empty;
            }
        }
    }
}