原文:

“What happens if we replace a

specific resource? Would that be reflected in all objects using the resource? And if not, can we

bind to the resource dynamically?”

接上篇博文，如果我们需要在C#代码中动态替换某个logical resource，我们该如何做呢？

如，Window的Resources属性赋值如下：

Button Click事件中Replace Window的key为"brush1"的Resources

private void OnReplaceBrush(object sender, RoutedEventArgs e)        {            var brush = new LinearGradientBrush();            brush.GradientStops.Add(new GradientStop(Colors.Pink, 0.2));            brush.GradientStops.Add(new GradientStop(Colors.Blue, 0.5));            brush.GradientStops.Add(new GradientStop(Colors.Violet, 0.8));                        this.Resources["brush1"] = brush;        }

点击按钮，程序没有任何反应，可以通过DynamicResource这个markup extension实现。

“Run the application and click on the button. You'll notice nothing happens. Now

change the StaticResource markup extension to DynamicResource on the

Rectangle:”

程序运行如下：

点击Button后：

附XAML和C#代码：

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Windows;using System.Windows.Controls;using System.Windows.Data;using System.Windows.Documents;using System.Windows.Input;using System.Windows.Media;using System.Windows.Media.Imaging;using System.Windows.Navigation;using System.Windows.Shapes;namespace DynamicallyBindingToALogicalResource{    /// 
    /// Interaction logic for MainWindow.xaml    /// 
    public partial class MainWindow : Window    {        public MainWindow()        {            InitializeComponent();        }        private void OnReplaceBrush(object sender, RoutedEventArgs e)        {            var brush = new LinearGradientBrush();            brush.GradientStops.Add(new GradientStop(Colors.Pink, 0.2));            brush.GradientStops.Add(new GradientStop(Colors.Blue, 0.5));            brush.GradientStops.Add(new GradientStop(Colors.Violet, 0.8));                        this.Resources["brush1"] = brush;        }    }}