Python面向对象(self参数、封装)

day24

面向对象三大特性：封装

self参数

class Bar:
    def foo(self, arg):
        print(self, arg)

x = Bar()
print(x)

x.foo(112358)
print('/////////////////////////////////////////')
y = Bar()
print(y)

y.foo(112)

#self指调用方法的对象

self指调用方法的对象

执行结果：

<__main__.Bar object at 0x7fae0e065780>
<__main__.Bar object at 0x7fae0e065780> 112358
/////////////////////////////////////////
<__main__.Bar object at 0x7fae0e065828>
<__main__.Bar object at 0x7fae0e065828> 112

Process finished with exit code 0

对象可以存值

class Bar:
    def foo(self, arg):
        print(self, self.name, self.age, arg)

x = Bar()
x.name = 'nizhipeng'
x.age = 18

x.foo(1123)

y = Bar()
y.name = 'nizsvsd'
y.age = 20

y.foo(113)

执行结果:

 <__main__.Bar object at 0x7fdadb4f5828> nizhipeng 18 1123

<__main__.Bar object at 0x7fdadb4f5860> nizsvsd 20 113

Process finished with exit code 0

封装（面向对象的三大特性之一）

class Bar:
    def foo(self, arg):
        print(self.name, self.age, arg)

obj = Bar()
#将公共变量封装进对象中
obj.name = "nizhipeng"
obj.age = "18"
obj.foo("112358")

将公共变量封装进对象中，为封装。

nizhipeng 18 112358

Process finished with exit code 0