c#中，在沒有已繫結的事件委託例項的情況下，移除事件委託。

目前涉及要移除事件包含：CellEndEdit/MouseClick/CellValueChanged/ProtectionWarning/ScrollPositionChanged/SelectionChanged

參照原理程式碼如下：

        /// <summary>
        /// 
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button12_Click(object sender, EventArgs e)
        {
            // 為按鈕新增兩個事件
            this.button13.Click += new EventHandler(button12_Click_1);
            this.button13.Click += new EventHandler(button12_Click_2);
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button12_Click_1(object sender, EventArgs e)
        {
            MessageBox.Show("1");
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button12_Click_2(object sender, EventArgs e)
        {
            MessageBox.Show("2");
        }        

        /// <summary>
        /// 
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button14_Click(object sender, EventArgs e)
        {
            // 檢索按鈕的事件，這裡單擊事件的名字是EventClick，要注意的
            Delegate[] invokeList = GetObjectEventList(this.button13, "EventClick");
            if (invokeList != null)
            {
                foreach (Delegate del in invokeList)
                {
                    typeof(Button).GetEvent("Click").RemoveEventHandler(this.button13, del);
                }
            }
        }        

        /// <summary>
        /// 獲取控制元件事件  
        /// </summary>
        /// <param name="p_Control">物件</param>
        /// <param name="p_EventName">事件名 EventClick EventDoubleClick </param>
        /// <returns>委託列</returns>
        public Delegate[] GetObjectEventList(Control p_Control, string p_EventName)
        {
            PropertyInfo _PropertyInfo = p_Control.GetType().GetProperty("Events", BindingFlags.Instance | BindingFlags.NonPublic);
            if (_PropertyInfo != null)
            {
                object _EventList = _PropertyInfo.GetValue(p_Control, null);
                if (_EventList != null && _EventList is EventHandlerList)
                {
                    EventHandlerList _List = (EventHandlerList)_EventList;
                    FieldInfo _FieldInfo = (typeof(Control)).GetField(p_EventName, BindingFlags.Static | BindingFlags.NonPublic);
                    if (_FieldInfo == null) return null;
                    Delegate _ObjectDelegate = _List[_FieldInfo.GetValue(p_Control)];
                    if (_ObjectDelegate == null) return null;
                    return _ObjectDelegate.GetInvocationList();
                }
            }
            return null;
        }
 

(typeof(DevExpress.XtraSpreadsheet.SpreadsheetControl)).GetFields(BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Instance)

寫了一段程式碼用於查詢事件在哪個屬性中，然後再基於上面的原理程式碼就可以實現在不知道委託例項的情況下移除某事件委託。

            StringBuilder sb = new StringBuilder();
            PropertyInfo[] propertyInfos = spreadsheetControl1.GetType().GetProperties(BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Public);
            List<string> eventNames = new List<string>()
            {
                "onCellBeginEdit",
                "onCellEndEdit",
                "onCellValueChanged",
                "onProtectionWarning",
                "onScrollPositionChanged",
                "onSelectionChanged"
            };
            foreach (PropertyInfo propertyInfo in propertyInfos)
            {
                object obj = propertyInfo.GetValue(spreadsheetControl1, null);
                if (obj == null) continue;
                foreach (string eventName in eventNames)
                {                    
                    FieldInfo fieldInfo = obj.GetType().GetField(eventName, BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Public);
                    if (fieldInfo != null)
                        sb.AppendLine(string.Format("事件名稱：{0}，屬性名稱：{1}", eventName, propertyInfo.Name));
                }
            }
            memoEdit1.Text = sb.ToString();
 

附幾個事件對應PropertyInfo名稱

            Dictionary<string, string> events = new Dictionary<string, string>()
            {
                {"onCellBeginEdit","InnerControl"},
                {"onCellEndEdit","InnerControl"},
                {"onCellValueChanged","InnerControl"},
                {"onProtectionWarning","InnerControl"},
                {"onScrollPositionChanged","DocumentModel"},
                {"onSelectionChanged","DocumentModel"}
            };

改寫的GetObjectEventList函式程式碼

        /// <summary>
        /// 獲取SpreadsheetControl中某事件已繫結的委託列表
        /// </summary>
        /// <param name="spreadsheetControl"></param>
        /// <param name="propertyName">擁有該事件的屬性名稱</param>
        /// <param name="eventName">事件名稱，一般字首on</param>
        /// <returns></returns>
        public Delegate[] GetObjectEventList(DevExpress.XtraSpreadsheet.SpreadsheetControl spreadsheetControl, string propertyName, string eventName)
        {
            PropertyInfo propInfo = spreadsheetControl.GetType().GetProperty(propertyName, BindingFlags.Instance | BindingFlags.NonPublic);
            if (propInfo == null) return null;

            object obj = propInfo.GetValue(spreadsheetControl, null);
            if (obj == null) return null;

            FieldInfo fieldInfo = obj.GetType().GetField(eventName, BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Instance);
            if (fieldInfo == null) return null;

            Delegate fieldValue = (Delegate)fieldInfo.GetValue(obj);
            if (fieldValue == null) return null;

            Delegate[] delegates = fieldValue.GetInvocationList();
            return delegates;
        }