RichTextBox 概述

使用 RichTextBox 控件可以显示或编辑流内容,包括段落、图像、表格等。 本主题介绍 TextBox 类,并提供有关如何在 Extensible Application Markup Language (XAML) 和 C# 中使用它的示例。

使用 TextBox 还是 RichTextBox?

RichTextBoxTextBox 都允许用户编辑文本,但两个控件用于不同场景。 当用户需要编辑带格式的文本、图像、表格或其他多种格式的内容时,RichTextBox 是更好的选择。 例如,编辑需要格式、图像等的文档、文章或博客时,最好使用 RichTextBox 来实现。 TextBox 需要的系统资源比 RichTextBox 少,因此非常适合只需要编辑纯文本的场景(例如在窗体中使用)。 有关详细信息,请参阅 TextBox 中的 TextBox 概述。 下表汇总了 TextBoxRichTextBox 的主要功能。

控制 实时拼写检查 上下文菜单 格式命令,例如 ToggleBold (Ctr+B) FlowDocument 内容,例如图像、段落、表格等
TextBox 不是。
RichTextBox

注意

虽然 TextBox 不支持与格式相关的命令(例如 ToggleBold (Ctr+B)),但是两个控件均支持许多基本命令,例如 MoveToLineEnd

后面将更详细地介绍上表中的功能。

创建 RichTextBox

下面的代码演示如何创建 RichTextBox,以供用户在其中编辑多种格式的内容。

<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

    <!-- A RichTextBox with no initial content in it. -->
    <RichTextBox />

</Page>

具体而言,在 RichTextBox 中编辑的内容是流内容。 流内容可包含许多类型的元素,包括带格式的文本、图像、列表和表格。 有关流文档的详细信息,请参阅流文档概述。 为了包含流内容,RichTextBox 托管 FlowDocument 对象,后者也包含可编辑的内容。 为了在 RichTextBox 中演示流内容,以下代码演示如何创建带有段落和某些加粗文本的 RichTextBox

<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

  <StackPanel>
    <RichTextBox>
      <FlowDocument>
        <Paragraph>
          This is flow content and you can <Bold>edit me!</Bold>
        </Paragraph>
      </FlowDocument>
    </RichTextBox>
  </StackPanel>

</Page>
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Documents;
namespace SDKSample
{
    public partial class BasicRichTextBoxWithContentExample : Page
    {
        public BasicRichTextBoxWithContentExample()
        {
            StackPanel myStackPanel = new StackPanel();

            // Create a FlowDocument to contain content for the RichTextBox.
            FlowDocument myFlowDoc = new FlowDocument();

            // Create a Run of plain text and some bold text.
            Run myRun = new Run("This is flow content and you can ");
            Bold myBold = new Bold(new Run("edit me!"));

            // Create a paragraph and add the Run and Bold to it.
            Paragraph myParagraph = new Paragraph();
            myParagraph.Inlines.Add(myRun);
            myParagraph.Inlines.Add(myBold);

            // Add the paragraph to the FlowDocument.
            myFlowDoc.Blocks.Add(myParagraph);

            RichTextBox myRichTextBox = new RichTextBox();

            // Add initial content to the RichTextBox.
            myRichTextBox.Document = myFlowDoc;

            myStackPanel.Children.Add(myRichTextBox);
            this.Content = myStackPanel;
        }
    }
}

Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Media
Imports System.Windows.Documents
Namespace SDKSample
    Partial Public Class BasicRichTextBoxWithContentExample
        Inherits Page
        Public Sub New()
            Dim myStackPanel As New StackPanel()

            ' Create a FlowDocument to contain content for the RichTextBox.
            Dim myFlowDoc As New FlowDocument()

            ' Create a Run of plain text and some bold text.
            Dim myRun As New Run("This is flow content and you can ")
            Dim myBold As New Bold(New Run("edit me!"))

            ' Create a paragraph and add the Run and Bold to it.
            Dim myParagraph As New Paragraph()
            myParagraph.Inlines.Add(myRun)
            myParagraph.Inlines.Add(myBold)

            ' Add the paragraph to the FlowDocument.
            myFlowDoc.Blocks.Add(myParagraph)

            Dim myRichTextBox As New RichTextBox()

            ' Add initial content to the RichTextBox.
            myRichTextBox.Document = myFlowDoc

            myStackPanel.Children.Add(myRichTextBox)
            Me.Content = myStackPanel

        End Sub
    End Class
End Namespace

下图显示了此示例的呈现效果。

RichTextBox with content

ParagraphBold 等元素可决定 RichTextBox 内部内容的显示方式。 当用户编辑 RichTextBox 内容时,此流内容会发生更改。 若要了解有关流内容的功能及其工作方式的详细信息,请参阅流文档概述

注意

RichTextBox 内部的流内容行为与其他控件中包含的流内容行为并不完全相同。 例如,RichTextBox 中没有列,因此没有自动调整大小行为。 另外,在 RichTextBox 中不能使用内置功能,例如搜索、查看模式、页面导航和缩放。

实时拼写检查

可以在 TextBoxRichTextBox 中启用实时拼写检查。 启用拼写检查时,任何拼写错误的字词下方都会出现红线(见下图)。

Textbox with spell-checking

若要了解如何启用拼写检查,请参阅在文本编辑控件中启用拼写检查

上下文菜单

默认情况下,TextBoxRichTextBox 都有一个上下文菜单,该菜单在用户在控件内右键单击时显示。 上下文菜单使用户可以剪切、复制或粘贴(见下图)。

TextBox with context menu

可以创建自己的自定义上下文菜单来重写默认的上下文菜单。 有关详细信息,请参阅在 RichTextBox 中定位自定义上下文菜单

编辑命令

用户可使用编辑命令为 RichTextBox 内的可编辑内容设置格式。 除了基本编辑命令,RichTextBox 还包括 TextBox 不支持的格式设置命令。 例如,在编辑 RichTextBox 时,用户可以按 Ctrl+B 来切换加粗文本格式。 有关完整的可用命令列表,请参阅 EditingCommands。 除了使用键盘快捷方式,还可以将命令与按钮之类的其他控件挂钩。 以下示例演示如何创建如何创建简单的工具栏,其中包含用户可用来更改文本格式的按钮。

<Window x:Class="RichTextBoxInputPanelDemo.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Height="400" Width="600"
    >
  <Grid>

    <!-- Set the styles for the tool bar. -->
    <Grid.Resources>
      <Style TargetType="{x:Type Button}" x:Key="formatTextStyle">
        <Setter Property="FontFamily" Value="Palatino Linotype"></Setter>
        <Setter Property="Width" Value="30"></Setter>
        <Setter Property="FontSize" Value ="14"></Setter>
        <Setter Property="CommandTarget" Value="{Binding ElementName=mainRTB}"></Setter>
      </Style>

      <Style TargetType="{x:Type Button}" x:Key="formatImageStyle">
        <Setter Property="Width" Value="30"></Setter>
        <Setter Property="CommandTarget" Value="{Binding ElementName=mainRTB}"></Setter>
      </Style>
    </Grid.Resources>

    <DockPanel Name="mainPanel">

      <!-- This tool bar contains all the editing buttons. -->
      <ToolBar Name="mainToolBar" Height="30" DockPanel.Dock="Top">

        <Button Style="{StaticResource formatImageStyle}" Command="ApplicationCommands.Cut" ToolTip="Cut">
          <Image Source="Images\EditCut.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="ApplicationCommands.Copy" ToolTip="Copy">
          <Image Source="Images\EditCopy.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="ApplicationCommands.Paste" ToolTip="Paste">
          <Image Source="Images\EditPaste.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="ApplicationCommands.Undo" ToolTip="Undo">
          <Image Source="Images\EditUndo.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="ApplicationCommands.Redo" ToolTip="Redo">
          <Image Source="Images\EditRedo.png"></Image>
        </Button>

        <Button Style="{StaticResource formatTextStyle}" Command="EditingCommands.ToggleBold" ToolTip="Bold">
          <TextBlock FontWeight="Bold">B</TextBlock>
        </Button>
        <Button Style="{StaticResource formatTextStyle}" Command="EditingCommands.ToggleItalic" ToolTip="Italic">
          <TextBlock FontStyle="Italic" FontWeight="Bold">I</TextBlock>
        </Button>
        <Button Style="{StaticResource formatTextStyle}" Command="EditingCommands.ToggleUnderline" ToolTip="Underline">
          <TextBlock TextDecorations="Underline" FontWeight="Bold">U</TextBlock>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="EditingCommands.IncreaseFontSize" ToolTip="Grow Font">
          <Image Source="Images\CharacterGrowFont.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="EditingCommands.DecreaseFontSize" ToolTip="Shrink Font">
          <Image Source="Images\CharacterShrinkFont.png"></Image>
        </Button>

        <Button Style="{StaticResource formatImageStyle}" Command="EditingCommands.ToggleBullets" ToolTip="Bullets">
          <Image Source="Images\ListBullets.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="EditingCommands.ToggleNumbering" ToolTip="Numbering">
          <Image Source="Images/ListNumbering.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="EditingCommands.AlignLeft" ToolTip="Align Left">
          <Image Source="Images\ParagraphLeftJustify.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="EditingCommands.AlignCenter" ToolTip="Align Center">
          <Image Source="Images\ParagraphCenterJustify.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="EditingCommands.AlignRight" ToolTip="Align Right">
          <Image Source="Images\ParagraphRightJustify.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="EditingCommands.AlignJustify" ToolTip="Align Justify">
          <Image Source="Images\ParagraphFullJustify.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="EditingCommands.IncreaseIndentation" ToolTip="Increase Indent">
          <Image Source="Images\ParagraphIncreaseIndentation.png"></Image>
        </Button>
        <Button Style="{StaticResource formatImageStyle}" Command="EditingCommands.DecreaseIndentation" ToolTip="Decrease Indent">
          <Image Source="Images\ParagraphDecreaseIndentation.png"></Image>
        </Button>

      </ToolBar>

      <!-- By default pressing tab moves focus to the next control. Setting AcceptsTab to true allows the 
           RichTextBox to accept tab characters. -->
      <RichTextBox Name="mainRTB" AcceptsTab="True"></RichTextBox>
    </DockPanel>
  </Grid>
</Window>

下图显示此示例的显示效果。

RichTextBox with ToolBar

检测内容何时更改

通常 TextChanged 事件应该用于检测 TextBoxRichTextBox 中文本的更改,而不是你可能认为的 KeyDown。 有关示例,请参阅检测 TextBox 中的文本何时更改

保存、加载和打印 RichTextBox 内容

以下示例演示如何将 RichTextBox 的内容保存到文件,将该内容加载回 RichTextBox,并打印内容。 下面是示例的标记。

<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  x:Class="SDKSample.SaveLoadPrintRTB" >

  <StackPanel>
    <RichTextBox Name="richTB">
      <FlowDocument>
        <Paragraph>
          <Run>Paragraph 1</Run>
        </Paragraph>
      </FlowDocument>
    </RichTextBox>

    <Button Click="SaveRTBContent">Save RTB Content</Button>
    <Button Click="LoadRTBContent">Load RTB Content</Button>
    <Button Click="PrintRTBContent">Print RTB Content</Button>
  </StackPanel>

</Page>

下面是该示例的隐藏代码。

using System;
using System.IO;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Media;

namespace SDKSample
{

    public partial class SaveLoadPrintRTB : Page
    {

        // Handle "Save RichTextBox Content" button click.
        void SaveRTBContent(Object sender, RoutedEventArgs args)
        {

            // Send an arbitrary URL and file name string specifying
            // the location to save the XAML in.
            SaveXamlPackage("C:\\test.xaml");
        }

        // Handle "Load RichTextBox Content" button click.
        void LoadRTBContent(Object sender, RoutedEventArgs args)
        {
            // Send URL string specifying what file to retrieve XAML
            // from to load into the RichTextBox.
            LoadXamlPackage("C:\\test.xaml");
        }

        // Handle "Print RichTextBox Content" button click.
        void PrintRTBContent(Object sender, RoutedEventArgs args)
        {
            PrintCommand();
        }

        // Save XAML in RichTextBox to a file specified by _fileName
        void SaveXamlPackage(string _fileName)
        {
            TextRange range;
            FileStream fStream;
            range = new TextRange(richTB.Document.ContentStart, richTB.Document.ContentEnd);
            fStream = new FileStream(_fileName, FileMode.Create);
            range.Save(fStream, DataFormats.XamlPackage);
            fStream.Close();
        }

        // Load XAML into RichTextBox from a file specified by _fileName
        void LoadXamlPackage(string _fileName)
        {
            TextRange range;
            FileStream fStream;
            if (File.Exists(_fileName))
            {
                range = new TextRange(richTB.Document.ContentStart, richTB.Document.ContentEnd);
                fStream = new FileStream(_fileName, FileMode.OpenOrCreate);
                range.Load(fStream, DataFormats.XamlPackage);
                fStream.Close();
            }
        }

        // Print RichTextBox content
        private void PrintCommand()
        {
            PrintDialog pd = new PrintDialog();
            if ((pd.ShowDialog() == true))
            {
                //use either one of the below
                pd.PrintVisual(richTB as Visual, "printing as visual");
                pd.PrintDocument((((IDocumentPaginatorSource)richTB.Document).DocumentPaginator), "printing as paginator");
            }
        }
    }
}

Imports System.IO
Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Documents
Imports System.Windows.Media

Namespace SDKSample

    Partial Public Class SaveLoadPrintRTB
        Inherits Page

        ' Handle "Save RichTextBox Content" button click.
        Private Sub SaveRTBContent(ByVal sender As Object, ByVal args As RoutedEventArgs)

            ' Send an arbitrary URL and file name string specifying
            ' the location to save the XAML in.
            SaveXamlPackage("C:\test.xaml")
        End Sub

        ' Handle "Load RichTextBox Content" button click.
        Private Sub LoadRTBContent(ByVal sender As Object, ByVal args As RoutedEventArgs)
            ' Send URL string specifying what file to retrieve XAML
            ' from to load into the RichTextBox.
            LoadXamlPackage("C:\test.xaml")
        End Sub

        ' Handle "Print RichTextBox Content" button click.
        Private Sub PrintRTBContent(ByVal sender As Object, ByVal args As RoutedEventArgs)
            PrintCommand()
        End Sub

        ' Save XAML in RichTextBox to a file specified by _fileName
        Private Sub SaveXamlPackage(ByVal _fileName As String)
            Dim range As TextRange
            Dim fStream As FileStream
            range = New TextRange(richTB.Document.ContentStart, richTB.Document.ContentEnd)
            fStream = New FileStream(_fileName, FileMode.Create)
            range.Save(fStream, DataFormats.XamlPackage)
            fStream.Close()
        End Sub

        ' Load XAML into RichTextBox from a file specified by _fileName
        Private Sub LoadXamlPackage(ByVal _fileName As String)
            Dim range As TextRange
            Dim fStream As FileStream
            If File.Exists(_fileName) Then
                range = New TextRange(richTB.Document.ContentStart, richTB.Document.ContentEnd)
                fStream = New FileStream(_fileName, FileMode.OpenOrCreate)
                range.Load(fStream, DataFormats.XamlPackage)
                fStream.Close()
            End If
        End Sub

        ' Print RichTextBox content
        Private Sub PrintCommand()
            Dim pd As New PrintDialog()
            If (pd.ShowDialog() = True) Then
                'use either one of the below      
                pd.PrintVisual(TryCast(richTB, Visual), "printing as visual")
                pd.PrintDocument(((CType(richTB.Document, IDocumentPaginatorSource)).DocumentPaginator), "printing as paginator")
            End If
        End Sub
    End Class
End Namespace

另请参阅