python - 调用属性 getter、setter、deleter - Python

Question

我收到错误“类型错误:'locationTile' 在尝试调用其 fdel() 方法时不是可调用对象。代码:

class GamePlayLocationTiles(object):
    """The stuff needed for game play"""
    _locationTiles = []

    def locationTiles():
        doc = "property locationTiles's doc string"
        def fget(self):
            return self._locationTiles[0]
        def fset(self, value):
            self._locationTiles = value[0]
        def fdel(self):
            del self._locationTiles[0]
        return locals()  # credit: David Niergarth
    locationTiles = property(**locationTiles())

    def __init__(self):
        self.fill_location_tiles_list()

不同的模块:

import game_play_model

class GamePlayController:
    """perform operations on the game_play_model"""

    def __init__(self):
        self.the_game_location_tiles = game_play_model.GamePlayLocationTiles()
        self.shuffle_location_tiles()


    def shuffle_location_tiles(self):
        self.the_game_location_tiles.locationTiles().fdel() //this line causes the error

def main():
    the_game_play_controller = GamePlayController()

if __name__ == '__main__':
    main()

只是尝试删除它作为使用 getter、setter、deleter 访问私有(private)变量的测试。

Answer 1

def shuffle_location_tiles(self):
    del self.the_game_location_tiles.locationTiles

---

不应直接调用fdel 函数。当实例尝试删除该属性时，它将为您调用。

例如，

class Foo(object):
    def x():
        def fget(self):
            """I'm the 'x' property."""
            return self._x

        def fset(self, value):
            self._x = value

        def fdel(self):
            print('deleting x')
            del self._x
        return locals()
    x = property(**x())

    def __init__(self):
        self._x = None


c = Foo()
del c.x
# deleting x

---

self.the_game_location_tiles.locationTiles() 引发错误

"Type error: 'locationTile' is not a callable

因为 self.the_game_location_tiles.locationTiles 调用 fget 并返回值 self._locationTiles[0]。该值恰好不可调用。

您可以使用 GamePlayLocationTiles.locationTiles 访问属性本身，并调用 fdel

GamePlayLocationTiles.locationTiles.fdel(self.the_game_location_tiles)

但是当你可以只使用语句时没有理由这样做

del self.the_game_location_tiles.locationTiles