call方法
class Student(object):
def __init__(self,name,scores,power):
self.name=name
self.scores=scores
self.power=power
def __call__(self, *args, **kwargs):
return '对象被调用...'
def __new__(cls, *args, **kwargs):
if not hasattr(cls, 'obj'):
cls.obj = object.__new__(cls)
return cls.obj
s1=Student('westos1',[100,90,80],100)
s2=Student('westos2',[90,100,70],200)
print(s1)
print(s2)
formats={
'ymd':'{d.year}-{d.month}-{d.day}',
'mdy':'{d.month}/{d.day}/{d.year}'
}
class Date(object):
def __init__(self,year,month,day):
self.year=year
self.month=month
self.day=day
def __format__(self, format_spec):
if not format_spec:
format_spec='ymd'
fmt=formats[format_spec]
return fmt.format(d=self)
d=Date(2018,9,9)
print(format(d))
print(format(d,'mdy'))
print(d.__format__('ymd'))
print(format(d, 'ymd'))
class Date(object):
def __init__(self, year, month, day):
self.year = year
self.month = month
self.day = day
def __format__(self, format_spec):
if not format_spec:
return "%s-%s-%s" %(self.year, self.month, self.day)
else:
if format_spec == 'ymd':
return "%s-%s-%s" %(self.year, self.month, self.day)
elif format_spec == 'dmy':
return "%s/%s/%s" %(self.day, self.month, self.year)
else:
return "error format"
d = Date(2018, 9, 9)
print(format(d))
print(format(d, 'ymd'))
print(format(d, 'dmy'))
print(d.__format__('ymd'))
print(format(d,'ymd'))
print('name:%s,age:%d,scores:%s' %('lijia',20,99))
print('name:%s,age:%d,scores:%s' %('haha',10,dict(a=1,b=2)))
print('name:%s,age:%d,scores:%s' %('haha',10,(1,2)))
print('name:{0},age:{2},scores:{1}'.format('westos',10,[99,90,98]))
print('name:{0},age:{1},scores:{1}'.format('redhat',20))
print('name:{0},id:{1:.3f}'.format('lijia',19.234567))
d={'max':100,'min':10,'niddle':50}
print('oldage:{max},yonugage:{min}'.format(max=100,min=10))
print('oldage:{max}'.format(**d))
point=(3,4,5)
print('x:{0[0]},y:{0[2]}'.format(point[::-1]))
class Book(object):
def __init__(self,name,author,state,location):
self.name=name
self.author=author
self.state=state
self.location=location
def __str__(self):
return 'Book(%s,%d)' %(self.name,self.state)
b=Book('python','lijia',1,'ID666')
print('name:{0.name},state:{0.state},location:{0.location}'.format(b))
实现类的切片和索引
class Student(object):
def __init__(self,name,scores):
self.name=name
self.scores=scores
def __getitem__(self, index):
print('获取索引对应的value值')
return self.name[index]
def __setitem__(self, index, value):
self.scores[index]=value
def __delitem__(self, index):
del self.scores[index]
def hello(self):
return 'hello'
s=Student('westos',[90,98,96])
print(s[1])
s[0]=100
print(s[0])
print(s.scores)
del s[0]
print(s.scores)
print(s.__dict__)
class Student(object):
def __init__(self,name,scores):
self.name=name
self.scores=scores
def __getitem__(self, key):
return self.__dict__[key]
def __setitem__(self, key, value):
self.__dict__[key]=value
def __delitem__(self, key):
del self.__dict__[key]
def hello(self):
return 'hello'
s=Student('westos',[90,98,97])
print(s.__dict__)
print(s['name'])
print(s['scores'])
s['name']='lijia'
print(s['name'])
del s['name']
print(s['name'])
class Student(object):
def __init__(self,name,scores):
self.name=name
self.scores=scores
def __getitem__(self, key):
return self.scores[key]
def __setitem__(self, key, value):
self.scores[key]=value
def __delitem__(self, key):
del self.scores[key]
s=Student('westos',[90,98,97])
print(s[1:3])
s[1:3]=[0,0]
print(s[:])
del s[:-1]
print(s[:])
print(s[0])
对象str和repr方法
class People(object):
def __init__(self,name,age):
self.name=name
self.age=age
print('创建对象成功')
def __del__(self):
print('删除对象成功')
def __repr__(self):
return 'People(%s)' %(self.name)
def __hello(self):
print('hello')
def world(self):
self.__hello()
if __name__=='__main__':
p1=People('lijia',20)
print(p1)
print(p1.__str__())
p1.world()
print(str(p1))
print(repr(p1))
构造方法和析构方法
class People(object):
def __init__(self,name,age):
self.name=name
self.age=age
print('创建对象成功...')
def __del__(self):
print('删除对象成功...')
if __name__=='__main__':
p1=People('lijia',20)
del p1
比较大小
class Student(object):
def __init__(self, name, scores, power):
self.name = name
self.scores = scores
self.power = power
def __add__(self, other):
self.power = self.power + other.power
return self
def __gt__(self, other):
return self.power > other.power
__ge__ = lambda self, other: self.power >= other.power
def __eq__(self, other):
return self.power == other.power
def __ne__(self, other):
return self.power != other.power
def __repr__(self):
return "Student:%s,%s" %(self.name, self.power)
def __len__(self):
return len(self.scores)
s1 = Student('westos1', [101,100], 100)
s2 = Student('westos2', [100,70,90], 101)
s3 = Student('westos3', [100,60,80], 80)
print(s1+s2)
print(s1>s2>s3)
print(s1==s2)
print(s1<s2)
print(len(s1))
类内部装饰器
class Book(object):
def __init__(self, name, author, state, bookIndex):
self.name = name
self.author = author
self.__state = state
self.bookIndex = bookIndex
def get_state(self):
if self.__state == 0:
return '已借出'
elif self.__state == 1:
return '未借出'
else:
return "状态异常"
def set_state(self, value):
if value in (0,1):
self.__state = value
def del_state(self):
print("is deleteing......")
def __str__(self):
return 'Book(%s, %d)' %(self.name, self.__state)
state = property(fget=get_state, fset=set_state, fdel=del_state)
b = Book('python', 'lijia', 1, 'Id666')
b.state=10
print(b.state)
print(b.get_state())
print(b.set_state(10))
print(b.get_state())
print(b.state)
b.state=0
print(b.state)
del b.state
重复连接和成员操作符
from collections import Iterable
class Student(object):
def __init__(self, name, scores):
self.name = name
self.scores = scores
self.power = 200
def __add__(self, other):
self.power = self.power + other.power
return self
def __mul__(self, other):
return self.power * other
def __contains__(self, item):
return item in self.scores
def __iter__(self):
return iter(self.scores)
def __repr__(self):
return "Student:%s,%s" % (self.name, self.power)
print('hello'+' '+'world')
print([1,2,3]+[4,5,6])
s1=Student('westos1',[90,90,98])
s2=Student('westos2',[100,20,80])
s3=Student('westos3',[19,20,90])
print(s1+s2+s3)
print(s1)
a=3
print(a*3)
s='a'
print(s*3)
print(s1*3)
print(s1.scores)
print(100 in s1)
print(90 not in s1)
for i in s1:
print(isinstance(s1,Iterable))