WPF RichTextBox - get whole word at current caret position

Question

I enabled spelling on my WPF richtextbox and I want to get the misspelled word at current caret position before the context menu with spelling suggestions is displayed.

Answer 1

The new way

    void richTextBox1_PreviewKeyDown(object sender, KeyEventArgs e)
    {
        if (e.Key == Key.Back)
        {
            TextPointer start = richTextBox1.CaretPosition;
            string text1 = start.GetTextInRun(LogicalDirection.Backward);
            TextPointer end = start.GetNextContextPosition(LogicalDirection.Backward);
            string text2 = end.GetTextInRun(LogicalDirection.Backward);

            richTextBox1.Selection.Select(start, end);
            richTextBox1.Selection.ApplyPropertyValue(TextElement.ForegroundProperty, Brushes.Black);
            richTextBox1.Selection.Select(start, start);
            //e.Handled = true;
        }
    }

Answer 2

Check this out http://www.dotnetfunda.com/articles/article842-spellchecker-in-wpf-.aspx

Right around here seems to discuss some options which may help your scenario: "Here we are using SpellingError class to get the Suggessions. CaretIndex returns the index where the carat is in the textbox. GetSpellingError can return SpellingError object only when the current Carat location has a word with errors and also SpellCheck is enabled for the TextBox. "

Answer 3

The old way

    private void richTextBox1_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.KeyCode == Keys.Back)
        {
            var z = this.richTextBox1.SelectionStart;
            var r = richTextBox1.Find(" ", 0, z, RichTextBoxFinds.None | RichTextBoxFinds.Reverse);
            var q = this.richTextBox1.Text.Substring(r + 1, z - r - 1);
            switch (q)
            {
                case "test":
                    this.richTextBox1.SelectionStart = r + 1;
                    this.richTextBox1.SelectionLength = z - r - 1;
                    this.richTextBox1.SelectionColor = Color.Black;
                    this.richTextBox1.SelectionStart += this.richTextBox1.SelectionLength;
                    this.richTextBox1.SelectionLength = 0;
                    //e.Handled = true;
                    break;
                default:
                    this.richTextBox1.SelectionStart = z;
                    break;
            }
        }
    }

Answer 4

For future reference:

void richTextBox1_PreviewKeyDown(object sender, KeyEventArgs e)
{
   var rtb = (RichTextBox)sender;
   var tr = rtb.GetSpellingErrorRange(rtb.CaretPosition);
   if(tr != null)
   {
       string spellingerror = tr.Text;
       //Do whatever
   }
}