What is the value-binding syntax in xaml? | I'm getting all learned up about binding in WPF. I'm having a lot of trouble debugging the parse errors in my xaml, though. Can somebody pretty please tell me what's wrong with this little piece? :



```
<Border Name="TrackBackground"
    Margin="0"
    CornerRadius="2"                     
    Grid.Row="1"
    Grid.Column="1"
    Background="BlanchedAlmond"
    BorderThickness="1"
    Height="{TemplateBinding Height}">

    <Canvas Name="PART_Track" Background="DarkSalmon" Grid.Row="1" Grid.Column="1">
        <Thumb Name="ThumbKnob" Height="{Binding ElementName=Part_Track, Path=Height, Mode=OneWay}" />
    </Canvas>
</Border>

```

It's the databinding that breaks. I get an `InvalidAttributeValue` exception for ThumbKnob.Height when I try to run this. I know I must be missing something fundamental. So fill me in, stackers, and my gratitude will be boundless.




---


Changing the ElementName didn't help. There must me something else I'm not getting.


I should mention that I'm testing this in Silverlight. The exact message I'm getting out of Internet Explorer is:


`XamlParseException: Invalid attribute value for property Height.`


This whole thing is inside a ControlTemplate. I'm making a slider control just to teach myself the concepts.