使用 XAML 设置器设置自定义附加属性

Question

I wanted to set a custom Attached Property that I attached to my Textboxes.

My name space is correctly imported, and used for other things in my UserControl so it works fine.

I can't seem to find the correct syntax for this.

Here is what I currently have (I tried to add brackets at different places, but it doesn't work):

... 
  <DataTrigger ...>
    <Setter ... />
    <Setter Property="(MyCustomXMLNS:TextBoxExtend).MyProperty" Value="..." />
  </DataTrigger>
</Style.Triggers>

This is only a syntax problem here, do you guys know how to achieve this?

Answer 1

You do not use parentheses in a Setter for an attached property, so the correct syntax is

<Setter Property="MyCustomXMLNS:TextBoxExtend.MyProperty" Value="..."/>

You would use parentheses when the property is the source of a Binding, like

<DataTrigger Binding="{Binding Path=(MyCustomXMLNS:TextBoxExtend.MyProperty)}"
             Value="...">