Python 结构类未定义，是否已使用？

这是tkinter游戏代码的一部分 已导入Random和tkinter模块。 我的问题是-

一,。 Struct类只进行了初始化，但没有定义，只是简单地传递了它，然后就被使用了

def run(rows, cols):
# create the root and the canvas
global canvas
root = Tk()
margin = 5
cellSize = 15
canvasWidth = 2*margin + cols*cellSize
canvasHeight = 2*margin + rows*cellSize+100
canvas = Canvas(root, width=canvasWidth, height=canvasHeight)
canvas.pack()
# Store canvas in root and in canvas itself for callbacks
root.canvas = canvas.canvas = canvas
# Set up canvas data and call init
class Struct: pass
canvas.data = Struct()
canvas.data.margin = margin
canvas.data.cellSize = cellSize
canvas.data.canvasWidth = canvasWidth
canvas.data.canvasHeight = canvasHeight
canvas.data.rows = rows
canvas.data.cols = cols
canvas.data.canvasWidth = canvasWidth
canvas.data.canvasHeight = canvasHeight
canvas.data.player1Score = 0
canvas.data.player2Score = 0
canvas.data.inGame = False
init()
# set up events
root.bind("<Key>", keyPressed)
timerFired()
# and launch the app
root.mainloop()  # This call BLOCKS (so your program waits until you close the window!)
run(40,40)

由于没有定义类，如何使用canvas.data.\uuuuuuuuuuuuuuuuuuuuuuuuu

问题：结构类未定义但已使用

您错了，

类结构已定义

此行定义了一个有效的对象：

class Struct: pass

以下两个示例是等效的

空对象

Struct

成为

canvas

属性，然后使用属性扩展对象

margin = 5

# Define the object
class Struct: pass

# Instantiate the object `Struct` 
# Assign the reference to the object `Struct` to the attribute `.data`
canvas.data = Struct()

# Assing the value `margin` to the attribute `.margin` of the object `Struct`
canvas.data.margin = margin

# Access the attribute `.margin` in the object `Struct`
print(canvas.data.margin)
# >>> 5

对象

Struct

使用预定义的

类结构

margin = 5

# Define the object
class Struct:
    def __init__(self, margin):
        self.margin = margin

# Instantiate the object `Struct` 
# Pass the value `margin` to it
# Assign the reference to the object `Struct` to the attribute `.data`
canvas.data = Struct(margin)

# Access the attribute `.margin` in the object `Struct`
print(canvas.data.margin)
# >>> 5

---

请修复已发布代码的缩进。感谢您的回答，但是我们如何访问画布的属性“.data”？@AppleKrumble:“访问画布的属性

.data

”*：

canvas.data

。不，我的意思是“canvas”是“canvas”类的对象，它是“Tkinter”模块的一部分。因此，“canvas.data”是对象“canvas”的一个属性，而对象“canvas”又变成了“Struct”类的对象？@AppleKrumble:你是在问如何才能在这里

.data

向

tkinter类canvas

实例对象，这里

canvas

添加一个属性？是的，有点像这样，在这种情况下会发生什么？

margin = 5

# Define the object
class Struct:
    def __init__(self, margin):
        self.margin = margin

# Instantiate the object `Struct` 
# Pass the value `margin` to it
# Assign the reference to the object `Struct` to the attribute `.data`
canvas.data = Struct(margin)

# Access the attribute `.margin` in the object `Struct`
print(canvas.data.margin)
# >>> 5