组合补充,主动调用其他类的成员,特殊成员
一丶组合补充
1.类或对象是否能做字典的key
1 class Foo: 2 pass 3 4 user_info = { 5 Foo:1, 6 Foo():5 7 } 8 9 print(user_info)
2.对象中到底有什么?
class Foo(object): def __init__(self,age): self.age = age def display(self): print(self.age) data_list = [Foo(8),Foo(9)] for item in data_list: print(item.age,item.display())
3.烧脑练习 top 1
class StarkConfig(object): def __init__(self,num): self.num = num def changelist(self,request): print(self.num,request) class RoleConfig(StarkConfig): def changelist(self,request): print('666') # 创建了一个列表,列表中有三个对象(实例) # [ StarkConfig对象(num=1), StarkConfig对象(num=2), RoleConfig对象(num=3) ] config_obj_list = [StarkConfig(1),StarkConfig(2),RoleConfig(3)] for item in config_obj_list: print(item.num)
4.烧脑练习top2
class StarkConfig(object): def __init__(self,num): self.num = num def changelist(self,request): print(self.num,request) class RoleConfig(StarkConfig): pass # 创建了一个列表,列表中有三个对象(实例) # [ StarkConfig对象(num=1), StarkConfig对象(num=2), RoleConfig对象(num=3) ] config_obj_list = [StarkConfig(1),StarkConfig(2),RoleConfig(3)] for item in config_obj_list: item.changelist(168)
5.烧脑练习top3
class StarkConfig(object): def __init__(self,num): self.num = num def changelist(self,request): print(self.num,request) class RoleConfig(StarkConfig): def changelist(self,request): print(666,self.num) # 创建了一个列表,列表中有三个对象(实例) # [ StarkConfig对象(num=1), StarkConfig对象(num=2), RoleConfig对象(num=3) ] config_obj_list = [StarkConfig(1),StarkConfig(2),RoleConfig(3)] for item in config_obj_list: item.changelist(168)
6.烧脑练习top4
class StarkConfig(object): def __init__(self,num): self.num = num def changelist(self,request): print(self.num,request) def run(self): self.changelist(999) class RoleConfig(StarkConfig): def changelist(self,request): print(666,self.num) config_obj_list = [StarkConfig(1),StarkConfig(2),RoleConfig(3)] config_obj_list[1].run() config_obj_list[2].run() # 666 3
7.烧脑练习top5
class StarkConfig(object): def __init__(self,num): self.num = num def changelist(self,request): print(self.num,request) def run(self): self.changelist(999) class RoleConfig(StarkConfig): def changelist(self,request): print(666,self.num) class AdminSite(object): def __init__(self): self._registry = {} def register(self,k,v): self._registry[k] = v site = AdminSite() print(len(site._registry)) # 0 site.register('range',666) site.register('shilei',438) print(len(site._registry)) # 2 site.register('lyd',StarkConfig(19)) site.register('yjl',StarkConfig(20)) site.register('fgz',RoleConfig(33)) print(len(site._registry)) # 5
8.烧脑练习top6
class StarkConfig(object): def __init__(self,num): self.num = num def changelist(self,request): print(self.num,request) def run(self): self.changelist(999) class RoleConfig(StarkConfig): def changelist(self,request): print(666,self.num) class AdminSite(object): def __init__(self): self._registry = {} def register(self,k,v): self._registry[k] = v site = AdminSite() site.register('lyd',StarkConfig(19)) site.register('yjl',StarkConfig(20)) site.register('fgz',RoleConfig(33)) print(len(site._registry)) # 3 for k,row in site._registry.items(): row.changelist(5)
9.烧脑练习top7
class StarkConfig(object): def __init__(self,num): self.num = num def changelist(self,request): print(self.num,request) def run(self): self.changelist(999) class RoleConfig(StarkConfig): def changelist(self,request): print(666,self.num) class AdminSite(object): def __init__(self): self._registry = {} def register(self,k,v): self._registry[k] = v site = AdminSite() site.register('lyd',StarkConfig(19)) site.register('yjl',StarkConfig(20)) site.register('fgz',RoleConfig(33)) print(len(site._registry)) # 3 for k,row in site._registry.items(): row.run()
10.烧脑练习top8
class UserInfo(object): pass class Department(object): pass class StarkConfig(object): def __init__(self,num): self.num = num def changelist(self,request): print(self.num,request) def run(self): self.changelist(999) class RoleConfig(StarkConfig): def changelist(self,request): print(666,self.num) class AdminSite(object): def __init__(self): self._registry = {} def register(self,k,v): self._registry[k] = v(k) site = AdminSite() site.register(UserInfo,StarkConfig) site.register(Department,StarkConfig) print(len(site._registry)) # 3 for k,row in site._registry.items(): row.run()
二丶主动调用其他类的成员
方法一:
class Base(object): def f1(self): print('5个功能') class Foo(object): def f1(self): print('3个功能') Base.f1(self) obj = Foo() obj.f1(
总结:Base.实例方法(自己上传self)
与继承能力无关
方法二:
class Foo(object): def f1(self): super().f1() print('3个功能') class Bar(object): def f1(self): print('6个功能') class Info(Foo,Bar): pass # obj = Foo() # obj.f1() obj = Info() obj.f1()
三丶特殊成员
1.类名() 自动执行__init__
class Foo(object): def __init__(self,a1,a2): self.a1 = a1 self.a2 = a2
obj = Foo(1,2)
2.对象() 自动执行__call__
def __call__(self, *args, **kwargs): print(11111,args,kwargs) return 123
ret = obj(6,4,2,k1 = 456)
3.对象['xx'] 自动执行__getitem__
def __setitem__(self, key, value): print(key,value,111111111) ret = obj['yu'] print(ret)
4.对象['xx'] = 11 自动执行__setitem__
def __setitem__(self, key, value): print(key,value,111111111) obj['k1'] = 123
5.del 对象[xx] 自动执行__delitem__
def __delitem__(self, key): print(key) del obj['uuu']
6.对象+对象 自动执行__add__
def __add__(self, other): return self.a1 + other.a2 obj1 = Foo(1,2) obj2 = Foo(88,99) ret = obj2 + obj1 print(ret)
7.with 对象 自动执行 __enter/__exit__
def __enter__(self): print('1111') return 999 def __exit__(self, exc_type, exc_val, exc_tb): print('22222') obj = Foo(1,2) with obj as f: print(f) print('内部代码')
8.__str__如果类中定义了__str__方法,那么打印对象时,默认该输出方法的返回值
class Foo: def __str__(self): return 1 obj = Foo() print obj # 输出:1
9.__doc__ 表示类的描述信息
class Foo: """ 描述类信息 """ def func(self): pass print Foo.__doc__ #输出:类的描述信息
10.__dict__ 类或者对象的所有成员
class Foo(object): def __init__(self,name,age): self.name = name self.age = age def func(self): pass obj1 = Foo('刘博文',99) obj2 = Foo('史雷',89) print(obj1.__dict__) # {'name': '刘博文', 'age': 99} print(obj2.__dict__) # {'name': '史雷', 'age': 89}
11.__iter__用于迭代器,之所以列表、字典、元组可以进行for循环,是因为类型内部定义了 __iter__
# l1是list类的一个对象,可迭代对象 l1 = [11,22,33,44] # l2是list类的一个对象,可迭代对象 l2 = [1,22,3,44] class Foo(object): def __init__(self,name,age): self.name = name self.age = age def func(self): pass def __iter__(self): # return iter([11,22,33,44,55,66]) yield 11 yield 22 yield 33 # obj1是Foo类的一个对象,可迭代对象 """ 如果想要把不可迭代对象 -> 可迭代对象 1. 在类中定义__iter__方法 2. iter内部返回一个迭代器(生成器也是一种特殊迭代器) """ obj1 = Foo('刘博文',99) for item in obj1: print(item)
12.真正的构造方法
class Foo(object): def __init__(self, a1, a2): # 初始化方法 """ 为空对象进行数据初始化 :param a1: :param a2: """ self.a1 = a1 self.a2 = a2 def __new__(cls, *args, **kwargs): # 构造方法 """ 创建一个空对象 :param args: :param kwargs: :return: """ return object.__new__(cls) # Python内部创建一个当前类的对象(初创时内部是空的.). obj1 = Foo(1,2) print(obj1) obj2 = Foo(11,12) print(obj2)