Automatic vertical scroll bar in WPF TextBlock?

Question

I have a TextBlock in WPF. I write many lines to it, far exceeding its vertical height. I expected a vertical scroll bar to appear automatically when that happens, but it didn't. I tried to look for a scroll bar property in the Properties pane, but could not find one.

How can I make vertical scroll bar created automatically for my TextBlock once its contents exceed its height?

Clarification: I would rather do it from the designer and not by directly writing to the XAML.

Answer 1

Wrap it in a scroll viewer:

<ScrollViewer>
    <TextBlock />
</ScrollViewer>

NOTE this answer applies to a TextBlock (a read-only text element) as asked for in the original question.

If you want to show scroll bars in a TextBox (an editable text element) then use the ScrollViewer attached properties:

<TextBox ScrollViewer.HorizontalScrollBarVisibility="Disabled"
         ScrollViewer.VerticalScrollBarVisibility="Auto" />

Valid values for these two properties are Disabled, Auto, Hidden and Visible.