小编Yar*_*rik的帖子

我需要将控件的属性绑定到XAML中的附加属性(以便附加属性成为绑定的源),我无法弄清楚如何做到 - VS2015给了我" 价值不会下降在预期范围内 "错误,当我运行应用程序时,我得到一个例外.

下面显示的技术在WPF中完美运行.

以下是演示此问题的示例应用程序.

AttachedPropertyTest.cs:

namespace App7
{
    public static class AttachedPropertyTest
    {
        public static readonly DependencyProperty FooProperty = DependencyProperty.RegisterAttached(
            "Foo", typeof(string), typeof(AttachedPropertyTest), new PropertyMetadata("Hello world!"));

        public static void SetFoo(DependencyObject element, string value)
        {
            element.SetValue(FooProperty, value);
        }

        public static string GetFoo(DependencyObject element)
        {
            return (string) element.GetValue(FooProperty);
        }
    }
}

MainPage.xaml中:

<!-- Based on the default MainPage.xaml template from VS2015.
     The only thing added is the TextBlock inside the Grid. -->
<Page x:Class="App7.MainPage"
      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
      xmlns:local="using:App7"
      xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
      xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" …