三。面向对象的 命名空间和作用域
class Person: # role = 'person' # 静态属性 # def __init__(self,name,sex,hp,ad): # self.name = name # 对象属性 属性 # self.sex = sex # self.hp = hp # self.ad = ad # def attack(self): # self.hobby = 'girl' # print('%s发起了一次攻击'%self.name) # # alex = Person('a_sb','不详',1,5) # alex.attack() # Person.attack(alex) # alex.age = 81 # # alex --> Person # # Person实例化了alex # print(alex.__dict__)
1.alex.name alex 指向自己的内存空间，在自己的内存空间中找name
2.alex.attack alex先找到自己的内存空间，然后再找到类对象指针，通过类对象指针找到类，再通过类找到attack
3.对象的内存空间里，只储存对象的属性，不能储存静态属性和方法
方法和静态属性都存储在类的内存空间中
# 为了节省内存，让多个对象去共享类中的资源
class Person: # role = 'person' # 静态属性 # def __init__(self,name,sex,hp,ad): # self.name = name # 对象属性 属性 # self.sex = sex # self.hp = hp # self.ad = ad # self.attack = 'hahaha' # def attack(self): # print('%s发起了一次攻击'%self.name) # # alex = Person('a_sb','不详',1,5) # boss_jin = Person('金老板','女',50,20) # print(alex.role) # print(boss_jin.role) # alex.role = 'dog' # print(alex.role) # print(boss_jin.role) # dog or ? person # class Person: # role = 'person' # 静态属性 # def __init__(self,name,sex,hp,ad): # self.name = name # 对象属性 属性 # self.sex = sex # self.hp = hp # self.ad = ad # self.attack = 'hahaha' # def attack(self): # print('%s发起了一次攻击'%self.name) # # alex = Person('a_sb','不详',1,5) # boss_jin = Person('金老板','女',50,20) # print(alex.role) # print(boss_jin.role) # alex.role = 'dog' # print(alex.role) # 模拟人生 # class Person: # money = 0 # def __init__(self,name): # self.name = name # def work(self): # print(self.name,'工作,赚了1000块钱') # Person.money += 1000 # # father = Person('father') # mother = Person('mother') # mother.work() # father.work() # print(Person.money) # 写一个类 完成一个功能 ： 可以统计这个类有几个对象 # class Foo: # count = 0 # def __init__(self): # Foo.count += 1 # f1 = Foo() # f2 = Foo() # f3 = Foo() # f4 = Foo() # f5 = Foo() # print(Foo.count) # # class Person: # money = [1] # def __init__(self,name): # self.name = name # def work(self): # print(self.name,'工作,赚了1000块钱') # self.money[0] += 1000 # # father = Person('father') # mother = Person('mother') # mother.work() # father.work() # print(Person.money) # 2000 or 0? # class Person: # money = [0] # def __init__(self,name): # self.name = name # def work(self): # print(self.name,'工作,赚了1000块钱') # Person.money = [Person.money[0] + 1000] # # father = Person('father') # mother = Person('mother') # mother.work() # father.work() # print(Person.money)
对象属性是独有的，静态属性和方法是共享的
# 对象使用名字：先找自己内存空间中的，再找类的内存空间中的
# 类名.静态变量名 ：对于静态属性的修改，应该使用类名直接修改