如何绑定到 Button BorderThickness？

Question

我在 xaml 中为 Button 类创建了一个自定义样式。以下是相关部分：

<Rectangle
    Stroke="{TemplateBinding BorderBrush}"
    StrokeThickness="{TemplateBinding BorderThickness}"/>

这显然行不通，因为StrokeThickness 是double，BorderThickness 是Thickness。

我怎样才能绑定到厚度的实际值（这将始终是统一的），而不会弄乱转换器？

在标记为完全重复之前，this question 是不同的。

Answer 1

试试这个：

<Rectangle
    Stroke="{TemplateBinding BorderBrush}"
    StrokeThickness="{Binding RelativeSource={RelativeSource TemplatedParent}, 
        Path=BorderThickness.Left}"/>

注意

以下绑定

{Binding RelativeSource={RelativeSource TemplatedParent}, Path=MyProperty}

与

相同

{TemplateBinding MyProperty}

Answer 2

怎么样

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:WpfApplication1"
        Title="MainWindow" Height="350" Width="525">
    <Window.Resources>
        <local:Con x:Key="abc" />
    </Window.Resources>
    <Grid>
        <Rectangle StrokeThickness="{Binding abc, Converter={StaticResource abc}}"/>
    </Grid>
</Window>


namespace WpfApplication1
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();

            DataContext = new { abc = new Thickness(4) };
        }
    }    

    public class Con : IValueConverter
    {
        public object Convert(object value, Type targetType, 
                              object parameter, 
                              System.Globalization.CultureInfo culture)
        {
            return ((Thickness)value).Left;
        }

        public object ConvertBack(object value, 
                                  Type targetType, 
                                  object parameter, 
                                  System.Globalization.CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
}