Modal Spell-Checking

To implement modal spell checking, you start by adding to your project a reference to the C1.Silverlight.SpellChecker assembly. Then, add the following code to your project:

Imports C1.Silverlight.SpellChecker

Public Partial Class MainPage

Inherits UserControl

' Spell-checker used by all controls on this page

Private _spell As New C1SpellChecker()

' Page constructor

Public Sub New()

' Regular Standard initialization

InitializeComponent()

' Load main spelling dictionary

AddHandler _spell.MainDictionary.LoadCompleted, AddressOf MainDictionary_LoadCompleted

_spell.MainDictionary.LoadAsync("C1Spell_en-US.dct")

' Load user dictionary

Dim ud As UserDictionary = _spell.UserDictionary

ud.LoadFromIsolatedStorage("Custom.dct")

' Other initializations

' ...

AddHandler App.Current.[Exit], AddressOf App_Exit

End Sub

End Class

using C1.Silverlight.SpellChecker;

public partial class MainPage : UserControl

// Spell-checker used by all controls on this page

  C1SpellChecker _spell = new C1SpellChecker();

// Page constructor

  public MainPage()

// Standard initialization

    InitializeComponent();

// Load main spelling dictionary

    _spell.MainDictionary.LoadCompleted += MainDictionary_LoadCompleted;

    _spell.MainDictionary.LoadAsync("C1Spell_en-US.dct");

// Load user dictionary

    UserDictionary ud = _spell.UserDictionary;

    ud.LoadFromIsolatedStorage("Custom.dct");

    App.Current.Exit += App_Exit;

// Other initializations

// ...

The code creates a new C1SpellChecker object to be shared by all controls on the page that require spell-checking.

Later, the page constructor invokes the LoadAsync method to load the main spell dictionary. In this case, we are loading C1Spell_en-US.dct, the American English dictionary. This file must be present on the application folder on the server. C1SpellChecker includes over 20 other dictionaries which can be downloaded from our site.

The code adds a handler to the SpellDictionaryBase.LoadCompleted event so it can detect when the main dictionary finishes loading and whether there were any errors. Here is a typical event handler:

void MainDictionary_LoadCompleted(object sender, OpenReadCompletedEventArgs e)

  if (e.Error != null)

MessageBox.Show("Error loading spell dictionary, " +

                    "spell-checking is disabled.");

The code also loads a user dictionary from isolated storage. This step is optional. The user dictionary stores words such as names and technical terms. The code attaches an event handler to the application's Exit event to save the user dictionary when the application finishes executing:

Once the dictionary has been loaded, you can invoke the modal spell-checker by calling the C1SpellChecker.CheckControlAsync method. For example:

Private Sub SpellCheck_Click(sender As Object, e As RoutedEventArgs)

AddHandler _spell.CheckControlCompleted, AddressOf _spell_CheckControlCompleted

_spell.CheckControlAsync(_rtb)

End Sub

Private Sub _spell_CheckControlCompleted(sender As Object, e As CheckControlCompletedEventArgs)

If Not e.Cancelled Then

Dim msg = String.Format("Spell-check complete. {0} error(s) found.", e.ErrorCount)

MessageBox.Show(msg, "Spell-check complete", MessageBoxButton.OK)

End If

End Sub

private void SpellCheck_Click(object sender, RoutedEventArgs e)

  _spell.CheckControlCompleted += _spell_CheckControlCompleted;

  _spell.CheckControlAsync(_rtb);

void _spell_CheckControlCompleted(object sender, CheckControlCompletedEventArgs e)

  if (!e.Cancelled)

    var msg = string.Format(

      "Spell-check complete. {0} error(s) found.", e.ErrorCount);

    MessageBox.Show(msg, "Spell-check complete..", MessageBoxButton.OK);

The code calls C1SpellChecker.CheckControlAsync. When the modal checking is complete, the C1SpellChecker.CheckControlCompleted event fires and shows a dialog box to indicate that the spell-checking operation is complete.