但是，我还想提供将 RichTextBox 中包含的文本的特定部分设为粗体的选项。这应该通过在 TextBox 中选择部分文本并按下按钮来完成，这将使所选文本变为粗体
有几种方法可以实现。目前看来您正在使用绑定关注mvvm，这是使用wpf 时的首选方式。考虑到这一点，您可以创建一个继承 RichTextBox 的新类并实现您需要的行为。
这是一个满足您需要的示例类：
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
namespace ChangeFontSelectionGridWPF
{
public class RichTextSelection : RichTextBox
{
public static readonly DependencyProperty DoBoldSelectionProperty = DependencyProperty.Register(
"DoBoldSelection", typeof(bool),
typeof(RichTextSelection),
new FrameworkPropertyMetadata(false, new PropertyChangedCallback(OnBoldSelectionChanged))
);
public bool DoBoldSelection
{
get => (bool)GetValue(DoBoldSelectionProperty);
set => SetValue(DoBoldSelectionProperty, value);
}
public RichTextSelection()
: base()
{
}
private static void OnBoldSelectionChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
RichTextSelection rchTextSel = (RichTextSelection)d;
if (rchTextSel.Selection != null)
rchTextSel.Selection.ApplyPropertyValue(TextElement.FontWeightProperty, FontWeights.Bold);
}
}
}
重新编译后，您可以将其添加为该列的DataTemplate，例如：
<DataTemplate>
<local:RichTextSelection Width="Auto"
AcceptsReturn="True"
DoBoldSelection="{Binding AllowBoldHighlight}"
>
<FlowDocument>
<Paragraph>
<Run Text="{Binding desc, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
</Paragraph>
</FlowDocument>
</local:RichTextSelection>
</DataTemplate>
您会注意到一个依赖属性：DoBoldSelection。此属性处理更改选定文本的字体粗细。在上面的示例中，该属性绑定到我的List<DescriptionObject> 中的一个属性，即AllowBoldHighlight。
我的DescriptionObject 类看起来像：
public class DescriptionObject : INotifyPropertyChanged
{
public string desc { get; set; } = string.Empty;
private bool allowHighlight = false;
public bool AllowBoldHighlight
{
get => allowHighlight;
set => SetProperty(ref allowHighlight, value);
}
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string propertyName) => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
protected bool SetProperty<T>(ref T storage, T value, [CallerMemberName] string propName = "")
{
if (EqualityComparer<T>.Default.Equals(storage, value)) return false;
storage = value;
OnPropertyChanged(propName);
return true;
}
}
MainWindow.xaml 看起来像：
<Window x:Class="ChangeFontSelectionGridWPF.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:ChangeFontSelectionGridWPF"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
Title="MainWindow"
Width="800"
Height="450"
mc:Ignorable="d"
>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<Button Grid.Row="0"
Grid.Column="1"
Margin="10"
Click="Button_Click"
Content="Bold"
/>
<DataGrid x:Name="DescriptionGrid"
Grid.Row="1"
Grid.ColumnSpan="2"
AutoGenerateColumns="False"
ItemsSource="{Binding Descriptions}"
>
<DataGrid.Columns>
<DataGridTemplateColumn Width="300" Header="Description">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<local:RichTextSelection Width="Auto"
AcceptsReturn="True"
DoBoldSelection="{Binding AllowBoldHighlight}"
>
<FlowDocument>
<Paragraph>
<Run Text="{Binding desc, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
</Paragraph>
</FlowDocument>
</local:RichTextSelection>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>
</DataGrid>
</Grid>
</Window>
MainWindow.cs 看起来像：
public partial class MainWindow : Window
{
public List<DescriptionObject> Descriptions { get; set; } = new List<DescriptionObject>();
public MainWindow()
{
InitializeComponent();
DataContext = this;
Descriptions.Add(new DescriptionObject() { desc = "Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo. Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?" });
Descriptions.Add(new DescriptionObject() { desc = "rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo. Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?" });
}
private void Button_Click(object sender, RoutedEventArgs e)
{
if (DescriptionGrid.SelectedItem is DescriptionObject dobj)
{
dobj.AllowBoldHighlight = true;
dobj.AllowBoldHighlight = false;
}
}
}
您会注意到在Button_Click 中您可以处理更改所选文本的FontWeight；基本示例。主要驱动力是dobj.AllowBoldHighlight = true。发生的情况是，当您选择/突出显示文本然后单击按钮时，dobj.AllowBoldHighlight 属性会发生更改，该更改会触发RichTextSelection 类中的OnBoldSelectionChanged。上面的示例使您可以灵活地在网格中的每个对象/实例上关闭和打开它。
这是它工作的一个短片：
希望这能帮助并解决您的问题，如果有任何问题，请告诉我。