RichTextBox Overview

Articolo
11/03/2006

The RichTextBox control enables you to display or edit flow content including paragraphs, images, tables, and more. This topic introduces the TextBox class and provides examples of how to use it in both Extensible Application Markup Language (XAML) and C#.

This topic contains the following sections.

TextBox or RichTextBox?
Creating a RichTextBox
Real-time Spell Checking
Context Menu
Editing Commands
Save, Load, and Print RichTextBox Content
Related Topics

TextBox or RichTextBox?

Both RichTextBox and TextBox allow users to edit text, however, the two controls are used in different scenarios. A RichTextBox is a better choice when it is necessary for the user to edit formatted text, images, tables, or other rich content. For example, editing a document, article, or blog that requires formatting, images, etc is best accomplished using a RichTextBox. A TextBox requires less system resources then a RichTextBox and it is ideal when only plain text needs to be edited (i.e. usage in forms). See TextBox Overview for more information on TextBox. The table below summarizes the main features of TextBox and RichTextBox.

Control	Real-time Spellchecking	Context Menu	Formatting commands like ToggleBold (Ctr+B)	FlowDocument content like images, paragraphs, tables, etc.
TextBox	Yes	Yes	No	No.
RichTextBox	Yes	Yes	Yes	Yes

Note: Although TextBox does not support formatting related commands like ToggleBold (Ctr+B), many basic commands are supported by both controls such as MoveToLineEnd.

The features from the table above are covered in more detail later.

Creating a RichTextBox

The code below shows how to create a RichTextBox that a user can edit rich content in.

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

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

</Page>

Specifically, the content edited in a RichTextBox is flow content. Flow content can contain many types of elements including formatted text, images, lists, and tables. See Flow Document Overview for in depth information on flow documents. In order to contain flow content, a RichTextBox hosts a FlowDocument object which in turn contains the editable content. To demonstrate flow content in a RichTextBox, the following code shows how to create a RichTextBox with a paragraph and some bolded text.

<Page xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="https://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;
            
        }
    }
}

The following illustration shows how this sample renders.

RichTextBox with content

Elements like Paragraph and Bold determine how the content inside a RichTextBox appears. As a user edits RichTextBox content, they change this flow content. To learn more about the features of flow content and how to work with it, see Flow Document Overview.

Note: Flow content inside a RichTextBox does not behave exactly like flow content contained in other controls. For example, there are no columns in a RichTextBox and hence no automatic resizing behavior. Also, built in features like search, viewing mode, page navigation, and zoom are not available within a RichTextBox.

Real-time Spell Checking

You can enable real-time spell checking in a TextBox or RichTextBox. When spellchecking is turned on, a red line appears underneath any misspelled words (see picture below).

Textbox with spell-checking

See How to: Enable Spellchecking in a Text Editing Control to learn how to enable spellchecking.

By default, both TextBox and RichTextBox have a context menu that appears when a user right-clicks inside the control. The context menu allows the user to cut, copy, or paste (see illustration below).

TextBox with context menu

You can create your own custom context menu to override the default one. See How to: Position a Custom Context Menu in a RichTextBox for more information.

Editing Commands

Editing commands enable users to format editable content inside a RichTextBox. Besides basic editing commands, RichTextBox includes formatting commands that TextBox does not support. For example, when editing in a RichTextBox, a user could press Ctr+B to toggle bold text formatting. See EditingCommands for a complete list of commands available. In addition to using keyboard shortcuts, you can hook commands up to other controls like buttons. The following example shows how to create a simple tool bar containing buttons that the user can use to change text formatting.

<Window x:Class="RichTextBoxInputPanelDemo.Window1"
    xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="https://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>

The following illustration shows how this sample displays.

RichTextBox with ToolBar

For the complete sample, see Create a RichTextBox with a Toolbar. In addition, see EditingCommands Sample for a demonstration of editing commands used with a RichTextBox.

Save, Load, and Print RichTextBox Content

The following example shows how to save content of a RichTextBox to a file, load that content back into the RichTextBox, and print the contents. Below is the markup for the example.

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

Below is the code behind for the example.

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");
            }
        }
    }
}

Condividi tramite

RichTextBox Overview

TextBox or RichTextBox?

Creating a RichTextBox

Real-time Spell Checking

Context Menu

Editing Commands

Save, Load, and Print RichTextBox Content

See Also

Concepts

Other Resources

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