Binding preference: Name or Type?

knowing that MyControl has a depProp. PX1, what binding should I prefeer, line1 or line2?

<UserControl x:Class="MyProject.MyControl"
             xmlns:my="clr-namespace:MyProject"

             x:Name="ParentControl">

    <Canvas>
        <Line x:Name="line1" 
              X1="{Binding RelativeSource={RelativeSource AncestorType={x:Type my:MyControl}}, Path=PX1}" />

        <Line x:Name="line2" 
              X1="{Binding ElementName=ParentControl, Path=PX1}" />

    </Canvas>
</UserControl>

I mean, should开发者_如何学JAVA we ensure the uniqueness of the name "ParentControl" per all possible parents in the second case?

I would prefer the latter syntax in most cases, as it's easier to read the intent, as long as you choose a clear name for the ParentControl. The down side is that this fails if you change the name, whereas the first will continue to work.

Side Note: PX1 doesn't actually need to be a DP, as long as the UserControl implements INotifyPropertyChanged and notifies when PX1 changes.