WPF 利用附加属性实现事件参数传递和引发

过程很简单，传递ViewModel到附加属性，附加属性引发相关事件和取消事件，从而引发VM中的委托。

  public class Attach
    {
        private static DependencyObject ElementUI;
        private static object Source;
        private static string SourceName;
        private static string EventName;
        private static Delegate dlg;

        public static readonly DependencyProperty EventNameProperty = DependencyProperty.RegisterAttached("EventName", typeof(string), typeof(Attach), new PropertyMetadata(null, new PropertyChangedCallback(OnEventNameValueChanged)));

        public static void SetEventName(DependencyObject d, object value) => d.SetValue(EventNameProperty, value);

        public static string GetEventName(DependencyObject d) => (string)d.GetValue(EventNameProperty);

        private static void OnEventNameValueChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            if (!e.NewValue.Equals(EventName))
                EventName = e.NewValue.ToString();
        }

        public static readonly DependencyProperty PushAttachProperty = DependencyProperty.RegisterAttached("PushAttach", typeof(bool), typeof(Attach), new PropertyMetadata(false, new PropertyChangedCallback(OnPushAttachValueChanged)));

        public static void SetPushAttach(DependencyObject d, bool value) => d.SetValue(PushAttachProperty, value);

        public static bool GetPushAttach(DependencyObject d) => (bool)d.GetValue(PushAttachProperty);
         

        private static void OnPushAttachValueChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            if ((bool)e.NewValue == true)
                DoAcion();
            if ((bool)e.NewValue == false)
                UnDoAcion();
        }
    
        
        private  static void UnDoAcion()
        {
            var uisource = ElementUI.GetType();
            var mothod = uisource.GetEvent(EventName);
            mothod.RemoveEventHandler(ElementUI, dlg);
            var getsource = Source.GetType();
            var sourcemothod = getsource.GetProperty(SourceName).GetValue(Source) as Action<object, EventArgs>;
            sourcemothod = null;
        }
        private static void DoAcion()
        {
            var getsource = ElementUI.GetType();
            var mothod = getsource.GetEvent(EventName);
            var k = Activator.CreateInstance(typeof(Attach));
            var local = k.GetType().GetMethod(nameof(EventMethod),BindingFlags.Public|BindingFlags.Instance);
             dlg = Delegate.CreateDelegate(mothod.EventHandlerType, k, local);
            mothod.AddEventHandler(ElementUI, dlg);
        }

        public  void EventMethod(object sender, EventArgs e)
        {
            var getsource = Source.GetType();
            var mothod = getsource.GetProperty(SourceName).GetValue(Source) as Action<object, EventArgs>;
            mothod?.Invoke(sender, e);
           
        }
        public static readonly DependencyProperty SourceProperty = DependencyProperty.RegisterAttached("Source", typeof(object), typeof(Attach), new PropertyMetadata(null, new PropertyChangedCallback(OnSourceValueChanged)));

        public static void SetSource(DependencyObject d, object value) => d.SetValue(SourceProperty, value);

        public static object GetSource(DependencyObject d) => (object)d.GetValue(SourceProperty);

        private static void OnSourceValueChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            if(ElementUI!=d)
            ElementUI = d;
            if(Source!=e.NewValue)
            Source = e.NewValue;
        }

        public static readonly DependencyProperty SourceNameProperty = DependencyProperty.RegisterAttached("SourceName", typeof(string), typeof(Attach), new PropertyMetadata(null, new PropertyChangedCallback(OnSourceNameValueChanged)));

        private static void OnSourceNameValueChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            if(e.NewValue!=null)
            if (!e.NewValue.Equals(SourceName))
                SourceName = e.NewValue.ToString();
        }

        public static void SetSourceName(DependencyObject d, object value) => d.SetValue(SourceNameProperty, value);

        public static string GetSourceName(DependencyObject d) => (string)d.GetValue(SourceNameProperty);

    }

xaml

<Button Height="120" VerticalAlignment="Top" Content="click" x:Name="b1"  local:Attach.Source="{Binding RelativeSource={RelativeSource Mode=Self},Path=DataContext}"  local:Attach.EventName="Click" local:Attach.SourceName="OnEvent" local:Attach.PushAttach="{Binding ElementName=cb1,Path=IsChecked}"/>
 <CheckBox Height="120" Content="click" x:Name="cb1" IsChecked="False" />

ViewMode中放置一个委托即可

    public class VMTest: INotifyPropertyChanged
    {
        protected void OnValueChanged(string Name) => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(Name));
        public event PropertyChangedEventHandler PropertyChanged;
     
        public Action<Object,EventArgs> OnEvent { get; set; }
        public VMTest（）
        {
           OnEvent =new  Action<Object,EventArgs>(OnEvent);
        }
        private void OnEvent(object arg1, EventArgs arg2)
        {
            MessageBox.Show("click");
        }
    }

效果图