无法删除 wpf 中的事件处理程序

在我的代码中，我做了下一件事：

        mouse_down = new MouseButtonEventHandler(Ship_Mouse_Down);
        mouse_move = new MouseEventHandler(Ship_Mouse_Move);
        mouse_up = new MouseButtonEventHandler(Ship_Mouse_Up);
        foreach (Image i in PlayerField.Children)
        {
            i.MouseUp += mouse_up;
            i.MouseDown += mouse_down;
            i.MouseMove += mouse_move;
            i.Source = (ImageSource)Resources["sea"];
        }

这会将处理程序添加到相应的图像。然后，当玩家按下按钮时，我这样做：

        foreach (Image i in PlayerField.Children)
        {
            i.MouseDown -= mouse_down;
            i.MouseUp -= mouse_up;
            i.MouseMove -= mouse_move;
        }

但似乎处理程序仍在运行，我不知道如何永久禁用它们。

foreach (Image i in PlayerField.Children)
{
    i.MouseUp -= mouse_up;
    i.MouseDown -= mouse_down;
    i.MouseMove -= mouse_move;
    i.MouseUp += mouse_up;
    i.MouseDown += mouse_down;
    i.MouseMove += mouse_move;
    i.Source = (ImageSource)Resources["sea"];
}