WPF 通过字典资源并使用动态绑定并控制全局字体大小

 public class FontSizeCollection : INotifyPropertyChanged
    {
        private DictionaryEntry fontsizedata;
        public DictionaryEntry FontSizeData
        {
            get { return fontsizedata; }
            set
            {
                fontsizedata = value;
                FontSizeName = value.Key.ToString();
                Size = (double)Application.Current.Resources[FontSizeName];
                PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("FontSizeName"));
                PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("Size"));
            }
        }
      
        public ICollection Collection
        {
            get
            {
                return Application.Current.Resources;
            }
           
        }
        private string ftsn;

        public string FontSizeName
        {
            get { return ftsn; }
            set
            {
                ftsn = value;
              
            }
        }

        private double size;

        public event PropertyChangedEventHandler PropertyChanged;

        public double Size
        {
            get { return size; }
            set
            {
                size = value;
                if (!string.IsNullOrWhiteSpace(FontSizeName))
                {
                    Application.Current.Resources[FontSizeName] = value;

                    PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("Size"));
                }
            }
        }
    }

    /// <summary>
    /// Window1.xaml 的交互逻辑
    /// </summary>
    public partial class Window1 : Window
    {
        private FontSizeCollection fsc = new FontSizeCollection();

        public Window1()
        {
            InitializeComponent();
            this.DataContext = fsc;

        }
    }

    <StackPanel Orientation="Vertical">
        <ListBox x:Name="lb1" SelectionMode="Single"  
                 SelectedItem="{Binding FontSizeData,Mode=TwoWay}"
                 ItemsSource="{Binding  Collection ,UpdateSourceTrigger=PropertyChanged}" DisplayMemberPath="Key">
        </ListBox>
        <TextBlock Text="{Binding  ElementName=lb1,  Path=SelectedItem.Key}"  />
        <TextBlock Text="{Binding Size}" />
        <Slider Value="{Binding Size, Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"   HorizontalAlignment="Stretch"  Minimum="0" Maximum="150"/>
    </StackPanel>