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TextBox in UserControl: "TextChanged" event does not see other controls

Posted By:      Posted Date: October 03, 2010    Points: 0   Category :WPF

I am building a UserControl with several TextBox controls. The behavior I'm looking for, is everytime a value is changed in any TextBox, the UserControl refreshes a couple labels contained within it. Here's the code behind file that does the work:

Public Sub Refresh(ByVal sender As Object, ByVal e As System.Windows.Controls.TextChangedEventArgs)
    lblTotalHours.Content = txtHours.Text
End Sub

Now, here's a way to hook it up that works, however, "PreviewTextInput" gives the old textbox value to Refresh() and not the new one (as expected). I'm just writing this example because I had to confirm that my method of linking the event worked - and it does. My application runs fine even though the result isn't what I am looking for: (edit: to make it work, i also adapted the Refresh() declaration to match the PreviewTextInput delegate to TextCompositionEventArgs, if I recall correctly...)

<UserControl ...>
        <Style TargetType="x:Key TextBox">
            <EventSetter Event="PreviewTextInput" Handler="Refresh" />
        <TextBox Name=&q

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