取得物件的私有欄位、呼叫已經綁定在物件上的事件

要 using System.Reflection、System.ComponentModel、System.Text 三個命名空間

public string ListFields(Type type)

{

  StringBuilder sb = new StringBuilder();

  FieldInfo[] fieldInfos = type.GetFields(BindingFlags.Static | BindingFlags.NonPublic);

  sb.Append(@"<table border='1' cellpadding='3' cellspacing='0'><tr><th>Field Name</th>

              <th>Type</th><th>Static</th></tr>");

  foreach (FieldInfo fInfo in fieldInfos)

  {

    sb.AppendFormat("<tr><td>{0:s}</td><td>{1:s}</td><td>{2:s}</td></tr>",

      fInfo.Name, fInfo.FieldType.FullName, fInfo.IsStatic ? "Yes" : "No");

  }

  sb.Append("</table>");

  return sb.ToString();

}

這樣就可以把 type 裡面定義的私有欄位，用 Table 的方式顯示出來
如果私有欄位定義在 base class 中，則傳入 obj.GetType().BaseType
執行範例一： 

System.Web.UI.WebControls.FormView() FormView1 = new System.Web.UI.WebControls.FormView();

ListFields(FormView1.GetType());

Field Name	Type	Static
EventPageIndexChanged	System.Object	Yes
EventPageIndexChanging	System.Object	Yes
EventItemCommand	System.Object	Yes
EventItemCreated	System.Object	Yes
EventItemDeleted	System.Object	Yes
EventItemDeleting	System.Object	Yes
EventItemInserting	System.Object	Yes
EventItemInserted	System.Object	Yes
EventItemUpdating	System.Object	Yes
EventItemUpdated	System.Object	Yes
EventModeChanged	System.Object	Yes
EventModeChanging	System.Object	Yes

執行範例二： 

System.Web.UI.WebControls.DropDownList DopDownList1 = new System.Web.UI.WebControls.DropDownList();

ListFields(DropDownList1.GetType());

Field Name	Type	Static

？？怎麼沒有東西？？
那麼改用 ListFields(dropDownList1.GetType().BaseType) 試看看

Field Name	Type	Static
EventSelectedIndexChanged	System.Object	Yes
EventTextChanged	System.Object	Yes

果然有了！
拿到這些私有欄位的名稱有什麼用？各位發覺到了嗎，這些私有欄位都是以 Event 開頭的，也就是說這些是用來儲存 Delegate 的私有變數
接下來，就可以利用以下的程式，來呼叫「已經綁定在物件上的事件處理函式」

public void InvokeEvent(object obj, Type type, string eventName, EventArgs e)

{  

  PropertyInfo propertyInfo = (type.GetProperty("Events", BindingFlags.Instance | BindingFlags.NonPublic));

  EventHandlerList eventHandlerList = (EventHandlerList)propertyInfo.GetValue(obj, null);

  FieldInfo fieldInfo = type.GetField(eventName, BindingFlags.Static | BindingFlags.NonPublic);

  Delegate[] dels = eventHandlerList[fieldInfo.GetValue(null)].GetInvocationList();

  foreach (Delegate d in dels)

  {  

    d.Method.Invoke(d.Target, new object[] { obj, e });

  }

}

呼叫範例：

InvokeEvent(DropDownList1, DropDownList1.GetType().BaseType, "EventSelectedIndexChanged", e);