Python staticmethod() Function
Python3 Built-in Functionsstaticmethod()It is a built-in function in Python used to convert a method into a static method.
A static method belongs to the class rather than instances; it does not need to access instance attributes or call instance methods.staticmethod()It can be used as a decorator, and can also be called directly.
Word Definition： staticmethodYesstatic methodAbbreviation for (static method).
Basic Syntax and Parameters
Syntax Format
staticmethod(function)
Parameter Description
- Parameter function：
- Type: Function object
- Description: The function to be converted into a static method.
Function Description
- Return value: Returns a static method object.
- Characteristics: Static methods do not require
selfthe self parameter, and can be called directly through the class name.
Example
Example 1: Basic Usage
Example
class MathUtils:
# Use decorator to define a static method (recommended)
@staticmethod
def add(a, b):
return a + b
@staticmethod
def multiply(a, b):
return a * b
# Call directly through the class name (no need to create an instance)
result = MathUtils.add(3, 5)
print(result) # Output: 8
result = MathUtils.multiply(4, 6)
print(result) # Output: 24
# Use decorator to define a static method (recommended)
@staticmethod
def add(a, b):
return a + b
@staticmethod
def multiply(a, b):
return a * b
# Call directly through the class name (no need to create an instance)
result = MathUtils.add(3, 5)
print(result) # Output: 8
result = MathUtils.multiply(4, 6)
print(result) # Output: 24
Expected output:
8 24
Code analysis:
- Static methods use
@staticmethodthe decorator to define. - Can be called like an ordinary function, but belongs to the class namespace.
- It can be called without creating an instance of the class.
Example 2: Not Using a Decorator
Example
class Temperature:
@staticmethod
def celsius_to_fahrenheit(c):
return c * 9/5 + 32
@staticmethod
def fahrenheit_to_celsius(f):
return (f - 32) * 5/9
# Call static method
print(Temperature.celsius_to_fahrenheit(0)) # Output: 32.0
print(Temperature.celsius_to_fahrenheit(100)) # Output: 212.0
print(Temperature.fahrenheit_to_celsius(32)) # Output: 0.0
# It can also be called through an instance
temp = Temperature()
print(temp.celsius_to_fahrenheit(25)) # Output: 77.0
@staticmethod
def celsius_to_fahrenheit(c):
return c * 9/5 + 32
@staticmethod
def fahrenheit_to_celsius(f):
return (f - 32) * 5/9
# Call static method
print(Temperature.celsius_to_fahrenheit(0)) # Output: 32.0
print(Temperature.celsius_to_fahrenheit(100)) # Output: 212.0
print(Temperature.fahrenheit_to_celsius(32)) # Output: 0.0
# It can also be called through an instance
temp = Temperature()
print(temp.celsius_to_fahrenheit(25)) # Output: 77.0
Expected output:
32.0 212.0 0.0 77.0
Code analysis:
- Static methods are often used in utility classes to encapsulate functions unrelated to instances.
- Static methods can be called via the class name or an instance name.
Example 3: Application in Factory Pattern
Example
class Person:
def __init__(self, name, age):
self.name = name
self.age = age
@staticmethod
def from_dict(data):
# Create a Person object from a dictionary
return Person(data['name'], data['age'])
@staticmethod
def create_adult(name):
# Create an adult
return Person(name, 18)
# Use a static method to create the object
p1 = Person.from_dict({'name': 'Tom', 'age': 20})
print(p1.name, p1.age) # Output: Tom 20
p2 = Person.create_adult('Jack')
print(p2.name, p2.age) # Output: Jack 18
def __init__(self, name, age):
self.name = name
self.age = age
@staticmethod
def from_dict(data):
# Create a Person object from a dictionary
return Person(data['name'], data['age'])
@staticmethod
def create_adult(name):
# Create an adult
return Person(name, 18)
# Use a static method to create the object
p1 = Person.from_dict({'name': 'Tom', 'age': 20})
print(p1.name, p1.age) # Output: Tom 20
p2 = Person.create_adult('Jack')
print(p2.name, p2.age) # Output: Jack 18
Expected output:
Tom 20 Jack 18
Static methods are often used as factory methods to create object instances from different data sources.
Other Extensions