python's twenty-third day for me 面对对象进阶

class A:
    def func1(self):pass
    def func2(self):pass
    def func3(self):pass
    def func4(self):pass

a = A()
b = A()
print(A.func1)      # <function A.func1 at 0x00000217A0BE3400>
print(a.func1)      # <bound method A.func1 of <__main__.A object at 0x00000217A0CF9EB8>>
print(b.func1)      # <bound method A.func1 of <__main__.A object at 0x00000217A0CFF080>>

class A:
    def func1(self):pass
    @classmethod
    def func2(cls):pass
    def func3(self):pass
    def func4(self):pass

a = A()
b = A()
print(A.func2)      # <bound method A.func2 of <class ‘__main__.A‘>>
print(a.func2)      # <bound method A.func2 of <class ‘__main__.A‘>>
print(b.func2)      # <bound method A.func2 of <class ‘__main__.A‘>>

#  对象能找到类，类里面绑着方法。

class A:
    def func1(self):pass
    @classmethod
    def func2(cls):pass
    def func3(self):pass
    @staticmethod
    def func4(self):pass

a = A()
b = A()
print(A.func4)      # <function A.func4 at 0x000002BE409837B8>
print(a.func4)      # <function A.func4 at 0x000002BE409837B8>
print(b.func4)      # <function A.func4 at 0x000002BE409837B8>

#  没有绑定  : 并没有 bound method  

#  能够检测到继承的关系。
class A:pass
class B(A):pass
class C(B):pass
c = C()
print(isinstance(c,C))      # True
print(isinstance(c,B))      # True
print(isinstance(c,A))      # True

# type 只是单纯的判断类
print(type(c) is C)     # True
print(type(c) is B)     # False
print(type(c) is A)     # False

# issubclasss(子类名，父类名) 返回bool值。
class A:pass
class B(A):pass
class C(B):pass
print(issubclass(B,A))      # True
print(issubclass(C,B))      # True
print(issubclass(C,A))      # True

class A:
    role = ‘Person‘
    def func(self):
        print(‘*‘)
# ret = input(‘>>>‘)
# a = A()
print(getattr(A,‘role‘))       # 从A的命名空间里找一个属性，直接就可以找到这个属性的值
f = getattr(A,‘func‘);f(1)     # 从A的命名空间找一个方法，找到的是这个方法的内存地址

class A:
    role = ‘Person‘
    def func(self):
        print(‘guxiaobai‘)
ret = input(‘>>>‘)
if hasattr(A,ret):
    f = getattr(A,ret)
    print(f)
    if type(f) is not str:
        f(1)  #  若是函数名则以加括号执行。
# 其次因为是从类中寻找的所以需要传参数。若是对象中找，则不需要传参数。
class A:
    role = ‘Person‘
    def func(self):
        print(‘guxiaobai‘)
ret = input(‘>>>‘)
a = A()
if hasattr(a,ret):
    f = getattr(a,ret)
    print(f)
    if type(f) is not str:
        f()

class A:
    role = ‘Person‘
    def func(self):
        print(‘guxiaobai‘)

print(hasattr(A,‘role‘))    # True
print(hasattr(A,‘func‘))    # True
ret = input(‘>>>‘)
if hasattr(A,ret):
    print(getattr(A,ret))

class A:                                 
    role = ‘Person‘                      
    def __init__(self):                  
        self.money = 100                 
    def func(self):                      
        print(‘guxiaobai‘)               
a = A()                                  
print(hasattr(a,‘money‘))   # True       
print(getattr(a,‘money‘))   # 100        
getattr(a,‘func‘)()         # guxiaobai 

import time     # 一个py文件就是一个模块
time.time()
print(getattr(time,‘time‘)())

def login():
    print(‘执行login功能‘)
def register():
    print(‘执行register功能‘)

import sys
while True:
    ret = input(‘请输入你想执行的功能：退出输入Q/q:‘)
    if ret.upper() == ‘Q‘:
        break
    if hasattr(sys.modules[‘__main__‘],ret):
        getattr(sys.modules[‘__main__‘],ret)()

class A:
    def __init__(self,name):
        self.name = name

    def func(self):
        print(‘guqingqiu‘)

a = A(‘顾清秋‘)
print(a.name)       # 顾清秋
setattr(a,‘name‘,‘顾小白‘)         # 已经存在的属性是修改。
print(a.name)       # 顾小白
print(a.__dict__)       # {‘name‘: ‘顾小白‘}
setattr(a,‘age‘,17)
print(a.__dict__)       # {‘age‘: 17, ‘name‘: ‘顾小白‘}
print(a.age)  # 17      # 不存在的属性就是新建。

def login():
    print(‘执行login功能‘)
class A:
    def __init__(self,name):
        self.name = name

    def func(self):
        print(‘guqingqiu‘)
a = A(‘顾清秋‘)
print(A.__dict__)
setattr(A,‘login‘,login)
print(A.__dict__)
getattr(A,‘login‘)()       # 外部login()中不需要形参。
getattr(a,‘login‘)()       # 外部login(self)中需要形参,否则会报错。

class A:
    def __init__(self,name):
        self.name = name
    def func(self):
        print(‘guqingqiu‘)
a = A(‘顾清秋‘)
print(a.__dict__)   # {‘name‘: ‘顾清秋‘}
delattr(a,‘name‘)
print(a.__dict__)   # {}

class A:
    def __init__(self,name,age,sex):
        self.name = name
        self.age = age
        self.sex = sex
    def __len__(self):
        return len(self.__dict__)
a = A(‘alex‘,35,‘不详‘)
print(a.__len__())  # 3
a.hobby = ‘开车‘
print(a.__len__())  # 4

# hash 和 __hash__关系
class A:
    def __init__(self,name,age):
        self.name = name
        self.age = age
    def __hash__(self):
        return 0       # return 是什么就是什么值。
a = A(‘alex‘,35)
print(hash(a))
print(a.__hash__())