You may try to use ScrollView. The code below demonstrates the idea. But I haven't come up with a solution to enable horizontal scrolling.
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Grid>
<ScrollViewer Height="100">
<DockPanel>
<TextBlock DockPanel.Dock="Left">
<TextBlock.Inlines>
1<LineBreak/>
2<LineBreak/>
3<LineBreak/>
4<LineBreak/>
5<LineBreak/>
6<LineBreak/>
7<LineBreak/>
8<LineBreak/>
9<LineBreak/>
10<LineBreak/>
11<LineBreak/>
12<LineBreak/>
13<LineBreak/>
</TextBlock.Inlines>
</TextBlock>
<TextBox AcceptsReturn="True" TextWrapping="Wrap">
I want a TextBox with line numbers. So I decided to use one small TextBox for the line numbers on the left and another big one on the rigth for the text. My problem now is that I put these two TextBoxes into a Dockpanel and I need a Heigth difference because the TextBox for the line numbers should not have scrollbars. So I need to short the left TextBox. My plan is to put an empty StackPanel below the left TextBox. And I'm getting trouble because the DockPanel doesen't sort my controls like i want. The only way I got it was using a fix width but I don't want that!
</TextBox>
</DockPanel>
</ScrollViewer>
</Grid>
</Window>
It looks like
