“全球”WinForms 事件

我有几个自定义控件的实例，这些实例在 MouseMove 上引发自定义事件。代码如下：事件参数类：

public class GroupMoveEventArgs
{
    public enum Action { CalcOffset, Move };
    Action action;
    int mouse_x;
    int mouse_y;
    // setters missed here
    public GroupMoveEventArgs(GroupMoveEventArgs.Action action,
        int mouse_x, int mouse_y)
    {
        this.action = action;
        this.mouse_x = mouse_x;
        this.mouse_y = mouse_y;
    }
}

控件类：

public delegate void GroupMoveEventHandler(object sender, GroupMoveEventArgs e);
public event GroupMoveEventHandler GroupMoveEvent;
protected virtual void figureMouseMove(object sender, MouseEventArgs e)
{
    if (mouseDown)
    {
        if (inGroup)
        {   // raising the event
            if (this.GroupMoveEvent != null)
                GroupMoveEvent(this, new GroupMoveEventArgs(
                               GroupMoveEventArgs.Action.Move,
                               Parent.PointToClient(Control.MousePosition).X,
                               Parent.PointToClient(Control.MousePosition).Y));
        }
    }
}
protected virtual void OnGroupMoveEvent(object sender, GroupMoveEventArgs e)
{
    Console.WriteLine("Got mouse move event " + this.num_of_points);
    if (inGroup)
    {
        if (e.EventAction == GroupMoveEventArgs.Action.Move)
        {
            Location = new Point(e.MouseX - offset.X, e.MouseY - offset.Y);
        }
        else
        if (e.EventAction == GroupMoveEventArgs.Action.CalcOffset)
        {
            Control c = sender as Control;
            Point pnt = Parent.PointToClient(Control.MousePosition);
            Point tmp = c.Location;
            offset.X = pnt.X - tmp.X;
            offset.Y = pnt.Y - tmp.Y;
        }
    }
}

问题是，当我引发一个事件时，它仅由发送者处理，而我需要所有控件来处理它。我该怎么做？

提前谢谢，伊万。