RichTextBox SelectionChanged firing twice!

Question

hello,

the richtextbox's SelectionChanged is getting fired twice .

basically the issue is , i am getting the font of the current selection inside this event , here is the code .

private void rta_SelectionChanged(object sender, RoutedEventArgs e)
    {

if (rta.Selection.GetPropertyValue(TextElement.FontSizeProperty) is double) { fontSize = (double)rta.Selection.GetPropertyValue(TextElement.FontSizeProperty); } }

i have setted the default fontsize to 12 , now , first time , fontsize value is 12 ( which is as expected ) , but second time , value is 11 .

here is the value of the XAML property of 1st and 2nd time .

1st

<Section xml:space="preserve" HasTrailingParagraphBreakOnPaste="False" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"&gt;&lt;Paragraph FontSize="11" FontFamily="Portable User Interface" Foreground="#FF000000" FontWeight="Normal" FontStyle="Normal" FontStretch="Normal" TextAlignment="Left"><Run FontSize="12" FontFamily="Arial" Text="l" /></Paragraph></Section>

2nd

<Section xml:space="preserve" HasTrailingParagraphBreakOnPaste="False" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"&gt;&lt;Paragraph FontSize="11" FontFamily="Portable User Interface" Foreground="#FF000000" FontWeight="Normal" FontStyle="Normal" FontStretch="Normal" TextAlignment="Left"><Run FontSize="12" FontFamily="Arial" Text="l" /></Paragraph></Section>

now , why is it firing twice , because its a rounted event ?

thanks

Jamal.

P.S

if you see the XAML closely , the fontsize of 11 is set for the paragraph .