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.netwpfsilverlightxamlbinding

What is the value-binding syntax in xaml?

I'm learning about binding in WPF. I'm having a lot of trouble debugging the parse errors in my xaml, though. 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.

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.

Solution

  • The ElementName property on a Binding is not supported in Silverlight.

    You will notice, if you go into the code behind or inspect the Binding object in class explorer, it doesn't have a property named ElementName.