Question

我正在尝试获取分配给控件的事件的名称例如：我有两种形式 A 和 B 。表格B 包含 GridControl ，而gridcontrol有一些事件，如 gridControl1_Validating

我的目标只是知道分配给控件的事件是什么

我的守则如下 FOrm A

 public Control[] FilterControls(Control start, Func<Control, bool> isMatch)
    {
        var matches = new List<Control>();
        Action<Control> filter = null;
        (filter = new Action<Control>(c =>
        {
            if (isMatch(c))
                matches.Add(c);
            foreach (Control c2 in c.Controls)
                filter(c2);
        }))(start);

        return matches.ToArray();


    }


     static void main[]
     {


        Control[] FoundControls = null;
        FoundControls = FilterControls(TF, c => c.Name != null && c.Name.StartsWith("grid"));

        var eventinfo = FoundControls[0].GetType().GetEvent("gridControl1.Validating", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);

     }

ON编译我得到了我的控制权但是我在 eventinfo 时变为空虽然gridcontrol事件在表单B

中有此事件

请帮忙

Answer 1

尝试"Validating"代替"gridControl1.Validating"“

var eventinfo = FoundControls[0].GetType().GetEvent(
    "Validating",
    BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);

虽然这与您已将事件处理程序附加到事件的事实无关。您正在获取事件本身，而不是附加的处理程序。您无法对eventInfo变量执行任何有用的操作（除了添加和删除其他事件处理程序之外）。

要访问附加的处理程序（底层委托），您需要查看事件实现的代码（使用反编译器，如Reflector或dotPeek，或使用Microsoft Reference Source）：

public event CancelEventHandler Validating
{
    add
    {
        base.Events.AddHandler(EventValidating, value);
    }
    remove
    {
        base.Events.RemoveHandler(EventValidating, value);
    }
}

事实证明，Control类使用类型为EventHandlerList的名为Events的属性来存储基于键的所有委托（{{1在这种情况下，字段）。

要检索事件的委托，我们应该从EventValidating属性中读取它们：

Events

和

public static Delegate[] RetrieveControlEventHandlers(Control c, string eventName)
{
    Type type = c.GetType();
    FieldInfo eventKeyField = GetStaticNonPublicFieldInfo(type, "Event" + eventName);
    if (eventKeyField == null)
    {
        eventKeyField = GetStaticNonPublicFieldInfo(type, "EVENT_" + eventName.ToUpper());
        if (eventKeyField == null)
        {
            // Not all events in the WinForms controls use this pattern.
            // Other methods can be used to search for the event handlers if required.
            return null;
        }
    }
    object eventKey = eventKeyField.GetValue(c);
    PropertyInfo pi = type.GetProperty("Events",
       BindingFlags.NonPublic | BindingFlags.Instance);
    EventHandlerList list = (EventHandlerList)pi.GetValue(c, null);
    Delegate del = list[eventKey];
    if (del == null)
        return null;
    return del.GetInvocationList();
}

// Also searches up the inheritance hierarchy
private static FieldInfo GetStaticNonPublicFieldInfo(Type type, string name)
{
    FieldInfo fi;
    do
    {
        fi = type.GetField(name, BindingFlags.Static | BindingFlags.NonPublic);
        type = type.BaseType;
    } while (fi == null && type != null);
    return fi;
}

最后一个方法将提取附加到控件事件的所有事件处理程序。这包括来自所有类的处理程序（甚至由winforms内部附加）。您还可以通过处理程序的目标对象筛选列表：

public static List<Delegate> RetrieveAllAttachedEventHandlers(Control c)
{
    List<Delegate> result = new List<Delegate>();
    foreach (EventInfo ei in c.GetType().GetEvents())
    {
        var handlers = RetrieveControlEventHandlers(c, ei.Name);
        if (handlers != null) // Does it have any attached handler?
            result.AddRange(handlers);
    }
    return result;
}

现在，您可以获取public static List<Delegate> RetrieveAllAttachedEventHandlersInObject(Control c, object handlerContainerObject) { return RetrieveAllAttachedEventHandlers(c).Where(d => d.Target == handlerContainerObject).ToList(); }中定义的gridControl1的所有事件处理程序：

formB

如何访问控件的事件？

1 个答案: