c# - 如何获取任意事件的调用列表

Question

如何在WPF中获取控件的委托(delegate)列表表单事件。

我试过下面的代码，但它会将字段信息返回为 null

TextBox cont = new TextBox();
cont.TextChanged += new TextChangedEventHandler(cont_TextChanged);
FieldInfo fi = cont.GetType().GetField("TextChanged", BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.GetField | BindingFlags.Public | BindingFlags.Static);
Delegate del = (Delegate)fi.GetValue(cont);

Answer 1

我不知道为什么人们说这是不可能的:

假设您想临时禁用任何事件，您可以创建这样的方法:

static Delegate[] DisableEvents(this Control ctrl, string eventName)
{
        PropertyInfo propertyInfo = ctrl.GetType().GetProperty("Events", BindingFlags.NonPublic | BindingFlags.Static | BindingFlags.Instance);
        EventHandlerList eventHandlerList = propertyInfo.GetValue(ctrl, new object[] { }) as EventHandlerList;
        FieldInfo fieldInfo = typeof(Control).GetField("Event"+eventName, BindingFlags.NonPublic | BindingFlags.Static);

        object eventKey = fieldInfo.GetValue(ctrl);
        var eventHandler = eventHandlerList[eventKey] as Delegate;
        Delegate[] invocationList = eventHandler.GetInvocationList();
        foreach (EventHandler item in invocationList)
        {
            ctrl.GetType().GetEvent(eventName).RemoveEventHandler(ctrl, item);
        }
        return invocationList;

}|

你可以这样调用它:

var events = textbox1.DisableEvents("GotFocus")

如果您想再次添加它们，您只需浏览事件列表即可。