如何使Style.Triggers触发要应用的不同命名样式

Lets say I have the below:

可以说我有以下内容：

<Style TargetType="{x:Type TextBox}">
    <Setter Property="BorderThickness" Value="1" />
    <Setter Property="BorderBrush" Value="Gray" />
    <Style.Triggers>
        <Trigger Property="IsFocused" Value="true"> 
            <Setter Property="BorderBrush" Value="Green" />
            <Setter Property="BorderThickness" Value="2" />
        </Trigger>
    </Style.Triggers> 
</Style>
<Styl