面向对象绑定方法和非绑定方法
绑定给对象的方法
class Student:
def __init__(self,name,age,gender):
self.name = name
self.age = age
self.gender = gender
def tell_info(self):
print('name:%s, age:%s, gender:%s' % (self.name, self.age, self.gender))
stu = Stedent('junjie', 18, 'male')
# 调用方法
stu.tell_info() # 就是 stu.tell_info(stu)
# 输出:name:junjie, age:18, gender:male
绑定给类的方法
class Student:
def __init__(self,name, age):
self.name = name
self.age = age
@classmethod # 该方法绑定给了类,以后由类来调用Student.from_cong()
def from_cong(cls): # 会自动将类名当做第一个参数传进来
# cls = Student
# obj = Student(settings.NAME, settings.AGE)
obj = cls(settings.NAME, settings.AGE)
return obj
import settings # 创造一个配置文件
obj = Student(settings.NAME, settings.AGE)
# print(obj.name)
# print(obj.age)
# obj1 = obj.from_cong()
# print(obj1.name)
obj1 = Student.from_cong()
print(obj1.name)
非绑定方法
class Student():
def __init__(self, name, age, gender):
self.name = name
self.age = age
self.gender = gender
self.id = self.create_id()
@staticmethod # 静态方法,不管是类来调用,还是对象来调用,都不会自动传递参数
def create_id():
import uuid
return uuid.uuid4()
s1 = Student('junjie', 18, 'male')
print(s1.__dict__)
# 输出{'name': 'junjie', 'age': 18, 'gender': 'male', 'id': UUID('12d9c400-61f4-42c6-8a74-fd8cb27c274a')}
Student.create_id()
隐藏属性
class Student():
__school = 'SH' # __类名__属性名 =》 _Student__school 使用__dict__查看
def __init__(self, name, age, gender):
self.name = name
self.age = age
self.gender = gender
# self.id = self.create_id()
# @staticmethod # 静态方法,不管是类来调用,还是对象来调用,都不会自动传递参数
def tell_info(self):
# if type(v) is not str:
# return
# self.__school = v
print('学校:%s, name:%s, age:%s, 性别:%s' % (self.__school, self.name, self.age, self.gender))
def get_school(self):
return self.__school
def set_school(self, v):
if type(v) is not str:
return
self.__school = v
s1 = Student('junjie', 18, 'male')
# print(s1.__dict__)
# print(s1.gender)
# print(s1.__dict__)
# s1.tell_info()
s1.set_school('haha')
s1.tell_info() # 学校:haha, name:junjie, age:18, 性别:male
# s1.tell_info('kkk')
# s1.tell_info()
property装饰器
class Student():
__school = 'SH' # _Student__school => _类名__属性名
def __init__(self, name, age):
self.__name = name
self.age = age
def __tell_info(self): # _Student__tell_info => _类名__函数名
print('name: %s, age: %s' % (self.__name, self.age))
@property # 把方法伪装成属性
def name(self):
return "name:%s" % self.__name
@name.setter
def name(self, v):
if type(v) is not str:
print('数据类型不合法')
# if isinstance(v, str):
return
self.__name = v
@name.deleter
def name(self):
print('不让删')
stu = Student('ly', 18)
print(stu.get_name())
stu.name = 123
print(stu.name)
del stu.name
# 练习
class Bmi():
def __init__(self, height, weight):
self.height = height
self.weight = weight
@property
def get_bmi(self):
return self.weight / (self.height ** 2)
bmi = Bmi(1.8, 70)
print(bmi.get_bmi)
# 了解
class Student():
__school = 'SH' # _Student__school => _类名__属性名
def __init__(self, name, age):
self.__name = name
self.age = age
def __tell_info(self): # _Student__tell_info => _类名__函数名
print('name: %s, age: %s' % (self.__name, self.age))
def get_name(self):
return "name:%s" % self.__name
def set_name(self, v):
if type(v) is not str:
print('数据类型不合法')
# if isinstance(v, str):
return
self.__name = v
def del_name(self):
print('不让删')
# 了解
name = property(get_name, set_name, del_name)
stu = Student('ly', 18)
# print(stu.xxx)
stu.name = 'aaa'
print(stu.name)