WPF provides the facility of spell checking. It is available in the following languages: English, Spanish, German and French. It can be enabled by setting the attached property SpellCheck.IsEnabled to true.

For Example:

<Grid>

<TextBox Height="23" HorizontalAlignment="Left" SpellCheck.IsEnabled="True" Language="en-US" Margin="10,10,0,0" Name="textBox1" VerticalAlignment="Top" Width="120" />

</Grid>

WPF spell check.png