Implementing Syncfusion WPF SpellChecker

SfSpellChecker provides a simple and intuitive interface to check for spelling errors in WPF text editor controls. It offers suggestions for misspelled words through dialog and context menu, supports multiple languages/cultures, custom dictionaries, and various ignore options.

When to Use This Skill

Use this skill when you need to:

• Add spell checking capability to WPF TextBox, RichTextBox, or other text editor controls
• Implement dialog-based or context menu-based spell checking
• Support multiple languages and cultures in spell checking
• Add custom dictionaries (Hunspell, Ispell, or OpenOffice formats)
• Configure ignore rules for emails, URLs, HTML tags, mixed case words, etc.
• Provide real-time spelling suggestions to users
• Customize spell checker appearance with themes
• Handle spell check completion events

Component Overview

Control: SfSpellChecker (Syncfusion.Windows.Controls.SfSpellChecker) Platform: WPF Namespace: Syncfusion.Windows.Controls Assembly: Syncfusion.SfSpellChecker.WPF

Key Capabilities:

• Dialog-based spell checking with suggestion list
• Context menu suggestions with right-click on error words
• Multi-language support with custom dictionaries
• Ignore options for special text patterns
• Custom word dictionary support
• Real-time error highlighting
• Replace, Ignore All, Add to Dictionary actions

Documentation and Navigation Guide

Getting Started

📄 Read: references/getting-started.md

• Installation and assembly deployment
• Adding SfSpellChecker to an application
• Attaching spell checker to TextBox
• First spell check with dialog
• Context menu setup
• Enable/disable spell checking
• Getting suggestions programmatically

Spell Check Methods

📄 Read: references/spell-check-methods.md

• Dialog-based spell checking
• Context menu-based suggestions
• PerformSpellCheckUsingDialog method
• Error word highlighting
• Replace and ignore operations
• Add to Dictionary functionality

Ignore Options

📄 Read: references/ignore-options.md

• Ignoring email addresses
• Ignoring URLs and internet addresses
• Ignoring HTML tags
• Ignoring mixed case words
• Ignoring uppercase words
• Ignoring alphanumeric words
• Configuration examples

Dictionary Support

📄 Read: references/dictionary-support.md

• Default English dictionary
• Multi-language spell checking
• Hunspell dictionary format
• Ispell dictionary format
• OpenOffice dictionary format
• Adding custom dictionaries
• Custom word lists
• Switching culture at runtime
• DictionaryCollection management

Customization and Theming

📄 Read: references/customization.md

• SpellCheckCompleted event
• Restricting completion message box
• Theme support with SfSkinManager
• ThemeStudio customization
• Visual appearance options

Quick Start

Basic Setup with Dialog

<Window xmlns:syncfusion="http://schemas.syncfusion.com/wpf">
    <Grid>
        <StackPanel>
            <TextBox 
                Text="Ths is a sampel text with speling errors."
                Name="textbox"
                TextWrapping="Wrap">
                
                <!--Attach SpellChecker to TextBox-->
                <syncfusion:SfSpellChecker.SpellChecker>
                    <syncfusion:SfSpellChecker 
                        x:Name="spellChecker"
                        EnableSpellCheck="True"/>
                </syncfusion:SfSpellChecker.SpellChecker>
            </TextBox>
            
            <Button 
                Content="Spell Check"
                Click="SpellCheck_ButtonClick"
                HorizontalAlignment="Center"/>
        </StackPanel>
    </Grid>
</Window>

// Code-behind
private void SpellCheck_ButtonClick(object sender, RoutedEventArgs e)
{
    spellChecker.PerformSpellCheckUsingDialog();
}

Quick Setup with Context Menu

<syncfusion:SfSpellChecker 
    x:Name="spellChecker"
    EnableSpellCheck="True"
    EnableContextMenu="True"/>

Users can right-click on error words (red underlined) to see suggestions.

Common Patterns

Pattern 1: Basic Spell Check with Dialog

// Create spell checker instance
SfSpellChecker spellChecker = new SfSpellChecker();
spellChecker.EnableSpellCheck = true;

// Attach to TextBox
SfSpellChecker.SetSpellChecker(textbox, spellChecker);

// Open spell check dialog
spellChecker.PerformSpellCheckUsingDialog();

Pattern 2: Context Menu with Ignore Options

SfSpellChecker spellChecker = new SfSpellChecker();
spellChecker.EnableSpellCheck = true;
spellChecker.EnableContextMenu = true;

// Configure ignore options
spellChecker.IgnoreUrl = true;
spellChecker.IgnoreEmailAddress = true;
spellChecker.IgnoreUpperCaseWords = true;

SfSpellChecker.SetSpellChecker(textbox, spellChecker);

Pattern 3: Multi-Language Support

// Create culture-specific spell checker
CultureInfo culture = new CultureInfo("fr-FR");
SfSpellChecker spellChecker = new SfSpellChecker();

// Add French dictionary
spellChecker.Dictionaries = new DictionaryCollection();
spellChecker.Dictionaries.Add(
    new HunspellDictionary()
    {
        Culture = culture,
        GrammarUri = new Uri("/MyApp;component/Dictionaries/fr-FR.aff", UriKind.Relative),
        DictionaryUri = new Uri("/MyApp;component/Dictionaries/fr-FR.dic", UriKind.Relative)
    }
);

spellChecker.Culture = culture;
SfSpellChecker.SetSpellChecker(textbox, spellChecker);

Pattern 4: Custom Dictionary

// Add custom words dictionary
Uri customDictUri = new Uri(Directory.GetCurrentDirectory() + 
                           @"\Dictionaries\CustomWords.txt", UriKind.Absolute);

spellChecker.Dictionaries.Add(
    new CustomDictionary()
    {
        Culture = new CultureInfo("en-US"),
        DictionaryUri = customDictUri
    }
);

Pattern 5: Handle Spell Check Completion

spellChecker.SpellCheckCompleted += (sender, e) =>
{
    // Suppress default message box
    (e as SpellCheckCompletedEventArgs).ShowMessageBox = false;
    
    // Custom completion logic
    MessageBox.Show("Spell check completed!", "Done");
};

Key Properties

Key Methods

Common Use Cases

1. Text Editor with Spell Check - Add comprehensive spell checking to WPF text editors
2. Multi-Language Document Editor - Support multiple languages with culture-specific dictionaries
3. Custom Domain Dictionary - Add industry-specific or company-specific terms
4. Email Client - Spell check with email/URL ignore options
5. HTML Editor - Spell check while ignoring HTML markup
6. Form Validation - Validate text input fields for spelling errors
7. Accessible Text Input - Provide context menu for easy error correction

Sample Applications

GitHub samples: WPF SpellChecker Examples