WPF equivalent to Windows Forms selection of length 0

Question

I am redoing my Windows Forms app in WPF and I am having some trouble with the Selections of Windows Forms and the TextRange of WPF. In Windows Forms, I used to do a Selection of Length 0 on a RichTextBox to change the color of a specific position so that when someone writes starting there it has a different color, withuot changing the color of any text. Something like this:

richTextBox.Select(position, 0);
richTextBox.SelectionColor = Color.Blue;

The problem is that in WPF I can't find any equivalent. If I use a TextRange of Length 0, it does nothing. Do you know what can I do? Thank you!

score 1 · Answer 1 · answered May 11 '20 at 02:43

You can try this aproach. It is not good but does it's work.

    Brush MyBrush = new SolidColorBrush(Colors.Black);
    private void Button_Click(object sender, RoutedEventArgs e)
    {
        MyBrush = new SolidColorBrush(Colors.Red);
        MyRichTextBox.Focus();
    }

    private void MyRichTextBox_TextChanged(object sender, TextChangedEventArgs e)
    {
        var textBox = (RichTextBox)sender;
        var docStart = textBox.Document.ContentStart.DocumentStart;
        foreach (var change in e.Changes)
        {

            var changeStart = docStart.GetPositionAtOffset(change.Offset, LogicalDirection.Forward);
            var changeEnd = docStart.GetPositionAtOffset(change.Offset + change.AddedLength, LogicalDirection.Forward);
            var changedRange = new TextRange(changeStart, changeEnd);

            changedRange.ApplyPropertyValue(TextElement.ForegroundProperty, MyBrush);

        }
    }

WPF equivalent to Windows Forms selection of length 0

1 Answers1