@classmethod裝飾器 (The @classmethod Decorator)

The @classmethod decorator is an inbuilt function decorator that gets evaluated after the function is defined. The result of the evaluation shadows the function definition. The @classmethod's first argument is always a class cls, similar to an instance method receiving self as its first argument.

@classmethod裝飾器是一個(gè)內(nèi)置的函數(shù)裝飾器，在定義函數(shù)后會(huì)對(duì)其進(jìn)行評(píng)估。 評(píng)估結(jié)果遮蓋了功能定義。 @classmethod的第一個(gè)參數(shù)始終是cls類(lèi)，類(lèi)似于將self作為其第一個(gè)參數(shù)的實(shí)例方法。

Syntax:

句法：

Class ABC(object):@classmethoddef function(cls, arg1, ...):...

• Exists to create class methods that are passed with the actual class object within the function call.

  存在以創(chuàng)建在函數(shù)調(diào)用中與實(shí)際類(lèi)對(duì)象一起傳遞的類(lèi)方法。

• Bound to the class and not to an instance.

  綁定到類(lèi)而不是實(shí)例。

• Can modify the class state and that would be applied across all the instances.

  可以修改類(lèi)狀態(tài)，并將其應(yīng)用于所有實(shí)例。

@staticmethod裝飾器 (The @staticmethod Decorator)

@staticmethods, similar to class methods, are methods that are bound to class rather than its object. However, they do not require a class instance creation. So, are not dependent on the state of the object.

與類(lèi)方法類(lèi)似， @staticmethods是綁定到類(lèi)而不是對(duì)象的方法。 但是，它們不需要?jiǎng)?chuàng)建類(lèi)實(shí)例。 因此，不依賴(lài)于對(duì)象的狀態(tài)。

Syntax:

句法：

Class ABC(object):@staticmethoddef function(arg1, arg2, ...):...

• Bound to the class and not to an instance

  綁定到類(lèi)而不是實(shí)例

• Cannot modify the class state

  無(wú)法修改類(lèi)狀態(tài)

@classmethod和@staticmethod之間的比較 (Comparison between @classmethod and @staticmethod)

Class methodStatic method

Takes cls as first parameter	Needs no specific parameters
Can access or modify the class state	Cannot access the class state
They must have parameters	Knows nothing about the class state. Are similar to utility methods.

類(lèi)方法 靜態(tài)方法

以cls作為第一個(gè)參數(shù)	不需要特定參數(shù)
可以訪問(wèn)或修改類(lèi)狀態(tài)	無(wú)法訪問(wèn)類(lèi)狀態(tài)
他們必須有參數(shù)	對(duì)類(lèi)狀態(tài)一無(wú)所知。 與實(shí)用程序方法相似。

@classmethod和@staticmethod的示例實(shí)現(xiàn) (Example implementation of @classmethod and @staticmethod)

class City: def __init__(self, zip_code, name): self.zip_code = name self.name = name # a class method to create a city object. @classmethoddef city_name(cls, zip_code, name): return cls(zip_code, name) # a static method to check if a city is capital or not@staticmethoddef isCapital(city_name): if city_name == 'bengaluru':return Trueif __name__ == '__main__':bengaluru = City(560086, 'bengaluru')mysuru = City.city_name(560111, 'mysuru')print("city is {}".format(bengaluru.name))print("city is {}".format(mysuru.name))print("Bengaluru is capital :{}".format(City.isCapital('bengaluru')))

Output

輸出量

city is bengaluru city is mysuru Bengaluru is capital : True

翻譯自: https://www.includehelp.com/python/staticmethod-vs-classmethod.aspx

總結(jié)

以上是生活随笔為你收集整理的Python中@staticmethod和@classmethod之间的区别的全部?jī)?nèi)容，希望文章能夠幫你解決所遇到的問(wèn)題。

如果覺(jué)得生活随笔網(wǎng)站內(nèi)容還不錯(cuò)，歡迎將生活随笔推薦給好友。