缺少Style.Triggers和x:类型.为什么？

Question

<TextBlock Text="{Binding MyTextProperty}">
    <TextBlock.Style>
        <Style TargetType="{x:Type TextBox}">
            <Style.Triggers>
                <DataTrigger Binding="{Binding MyTextProperty}" Value="{x:Null}">
                    <Setter Property="Text" Value="Hey, the text should not be empty!" />
                    <Setter Property="Foreground" Value="Red" />
                </DataTrigger>
            </Style.Triggers>
        </Style>
    </TextBlock.Style>
</TextBlock>

问题1:为什么要<Style TargetType="{x:Type TextBox}">给出错误The type 'x:Type' was not found. Verify that you are not missing an assembly reference and that all referenced assemblies have been built.

问题2:为什么我收到错误 The attachable property 'Triggers' was not found in type 'Style'.

我错过了什么吗？

Answer 1

看起来您正在尝试在Silverlight中使用WPF XAML.Silverlight不支持{x:Type}标记扩展.你可以改用TargetType={TextBox}.

此外,Silverlight没有DataTrigger支持!

看到:

什么是Silverlight中DataTrigger的替代品