Here is a sample code.
<TextBox Height="23" HorizontalAlignment="Left" Margin="12,0,0,0" Name="textBox1" VerticalAlignment="Top" Width="120" Text="{Binding ElementName=slider1, StringFormat=0, Path=Value, ValidatesOnDataErrors=True, UpdateSourceTrigger=PropertyChanged}" />
<Slider Height="23" HorizontalAlignment="Left" Margin="12,35,0,0" Name="slider1" VerticalAlignment="Top" Width="100" />
Hope this will help you...!!!