1、反射

用字符串来操作类或者对象的属性

class People: #     country= 'china' #     def __init__(self,name): #         self.name= name # #     def eat(self): #         print('%s is eating'%(self.name)) # peo1= People ('qqc') (1)hasattr print(hasattr(peo1,'name')) #判断name是否在peo1.name中是可以访问的属性

(2)getarrt

print(getattr(peo1,'xx','None'))#在peo1中没有xx这个属性，返回None，不会报错 (3)strattr

setattr(peo1,'age',19)    #增加属性 # print(peo1 .__dict__ ) (4)delattr(peo1,'name')  #删除

2、1.内置方法__str__

class People: # #     def __init__(self,name,age): # #         self.name = name # #         self.age= age # #     #在对象self被打印时，自动触发 ,应该在方法内采集与对象self有关的信息，然后拼成字符串返回 # #     def __str__(self): # #         return '姓名%s,年龄%s'%(self.name,self .age) # # # # obj = People ('qqc',33) # # print(obj)

2、2.内置方法__del__

__del__析构方法 # class People: #      def __init__(self,name,age): #         self.name = name #         self.age= age #         self.f= open('q.txt','rt',encoding= 'utf-8') #      def __del__(self): #          #做回收系统资源相关的事情 #          self.f.close() #          print('ggg') # # obj = People('egon',18) # del obj