自定义 DependencyProperty 与 RoutedEvent

Posted 2020-12-29 lonelyxmas

原文:自定义 DependencyProperty 与 RoutedEvent

    //自定义依赖属性
    class MyBook : DependencyObject//依赖属性必须派生自DependencyObject
    {
        public static readonly DependencyProperty BookNameProperty = DependencyProperty.Register("BookName", typeof(string), typeof(MyBook));//依赖属性必须是静态的DependencyObject对象
        public string BookName
        {
            get { return (string)GetValue(BookNameProperty); }
            set { SetValue(BookNameProperty, value); }
        }

        static MyBook()//静态构造函数
        {
            //BookNameProperty = DependencyProperty.Register("BookName", typeof(string), typeof(MyBook));
        }
    }

/*
 定义、注册、包装路由事件

WPF事件模型与WPF属性模型类似，与依赖项属性一样，路由事件由只读的静态字段表示，在静态构造函数中注册，并且通过一个标准的.NET事件定义进行包装*/

class MyButton : Button
    {
        //自定义路由事件
        public static readonly RoutedEvent HitEvent = EventManager.RegisterRoutedEvent("Hit", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(MyButton));
        public event RoutedEventHandler Hit
        {
            add { AddHandler(HitEvent, value); }
            remove { RemoveHandler(HitEvent, value); }
        }

        static MyButton()
        {
            //HitEvent = EventManager.RegisterRoutedEvent("Hit", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(MyButton));
        }

        public void RaiseRoutedEvent()
        {
            RoutedEventArgs routedEventArgs = new RoutedEventArgs(MyButton.HitEvent);
            //UIElement.RaiseEvent(RoutedEventArgs routedEeventArgs)方法
            this.RaiseEvent(routedEventArgs);//触发路由事件方法
        }

        //自定义普通事件
        //public delegate void EventHandler(object sender, EventArgs e);
        public event EventHandler SelectingButton;

        protected override void OnClick()
        {
            base.OnClick();

            RaiseRoutedEvent();//调用RaiseRoutedEvent()方法引发路由事件

            if (SelectingButton != null)
                SelectingButton(this, null);//调用SelectingButton(this, null)引发普通事件
        }
    }