• C# 清除事件绑定的函数


     

    方法一:
    代码
            /// <summary>
            /// 删除指定控件的指定事件
            /// </summary>
            /// <param name="control"></param>
            /// <param name="eventname"></param>
            public void ClearEvent(System.Windows.Forms.Control control, string eventname)
            {
                if (control == null) return;
                if (string.IsNullOrEmpty(eventname)) return;
    
                BindingFlags mPropertyFlags = BindingFlags.Instance | BindingFlags.Public | BindingFlags.Static | BindingFlags.NonPublic;
                BindingFlags mFieldFlags = BindingFlags.Static | BindingFlags.NonPublic;
                Type controlType = typeof(System.Windows.Forms.Control);
                PropertyInfo propertyInfo = controlType.GetProperty("Events", mPropertyFlags);
                EventHandlerList eventHandlerList = (EventHandlerList)propertyInfo.GetValue(control, null);
                FieldInfo fieldInfo = (typeof(System.Windows.Forms.Control)).GetField("Event" + eventname, mFieldFlags);
                Delegate d = eventHandlerList[fieldInfo.GetValue(control)];
    
                if (d == null) return;
                EventInfo eventInfo = controlType.GetEvent(eventname);
    
                foreach (Delegate dx in d.GetInvocationList())
                    eventInfo.RemoveEventHandler(control, dx);
    
            }
    调用:ClearEvent(button1,"Click");//就会清除button1对象的Click事件的所有挂接事件。
     
    方法二,写一个操作类,记录添加的事件列表,删除时从事件列表中读取出来然后删除.
     
    代码
    class MyEventManager:IDisposable
        {
            EventHandlerList eventList = new EventHandlerList();
            Hashtable eventObjectList = new Hashtable();
            public void AddEvent(Control control, string eventname, EventHandler eventhandler)
            {
                string keystr = control.Name + eventname;
                if (!eventObjectList.Contains(keystr)) eventObjectList.Add(keystr, new object());
                object eventObject = eventObjectList[keystr];
                switch (eventname)
                {
                    case "Click":
                        control.Click += eventhandler;
                        break;
                    case "Enter":
                        control.Enter += eventhandler;
                        break;
                        //...
                        //这里可以添加更多的事件支持,这都是因为C# 不支持宏替换而采用的无奈之举
                        //当然用反射也可以,不过用反射就没必要用这种方法了。
                }
                eventList.AddHandler(eventObject, eventhandler);
            }
            public void DelEvent(Control control, string eventname)
            {
                string keystr = control.Name + eventname;
                object eventObject = eventObjectList[keystr];
                Delegate d = eventList[eventObject];
                if (d == null) return;
                foreach (Delegate dd in d.GetInvocationList())
                {
                    switch (eventname)
                    {
                        case "Click":
                            control.Click -= (EventHandler)dd;
                            break;
                        case "Enter":
                            control.Enter -= (EventHandler)dd;
                            break;
                        //...
                        //这里可以添加更多的事件支持,这都是因为C# 不支持宏替换而采用的无奈之举
                        //当然用反射也可以,不过用反射就没必要用这种方法了。
                    }
    
                }
    
                eventList.RemoveHandler(eventObject, d);
                eventObjectList.Remove(eventObject);
            }
    }

     

     

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  • 原文地址:https://www.cnblogs.com/C-CHERS/p/10717876.html
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