You want to make tooltip . wpf.200things has an excellent record on it.
From this article. Basically you will create a tooltip as shown below.
<TextBox Text="Now is the winter of our discontent etc" Width="100" Margin="10"> <TextBox.ToolTip> <ToolTip DataContext="{Binding Path=PlacementTarget, RelativeSource={x:Static RelativeSource.Self}}"> <StackPanel> <Label FontWeight="Bold" Content="Full Text"/> <Label Content="{Binding Text}"/> <Label Content="--Gloster, in Richard III (Act I, Scene I)"/> </StackPanel> </ToolTip> </TextBox.ToolTip> </TextBox>
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