python中的iter迭代

具体解释了怎么用迭代&＃xff0c;怎样用迭代&＃xff0c;怎样转换成迭代&＃xff0c;可以看看

• 列表&＃xff0c;字典&＃xff0c;元组&＃xff0c;字符串&＃xff0c;集合可以使用迭代
• 自定义类中可以定义iter方法,来使用迭代
• iter方法意为可以迭代
• iterator意为定义迭代的对象&＃xff08;既有__iter__方法&＃xff0c;也有__next__方法&＃xff09;

(一)

from collections.abc import Iterable
from collections.abc import Iteratorimport time
class Person(object):def __init__(self):self.names &＃61; list()self.current_num &＃61; 0def add_person(self,name):self.names.append(name)def __iter__(self):#passreturn PersonsIterator(self)class PersonsIterator(object):def __init__(self,obj):self.obj &＃61; objself.current_num &＃61; 0def __iter__(self):passdef __next__(self):#pass#return 12345if self.current_num p1.add_person(&＃39;张三&＃39;)
p1.add_person(&＃39;李四&＃39;)
p1.add_person(&＃39;王五&＃39;)p_iter &＃61; iter(p1)
while True:try:ret &＃61; next(p_iter)print(ret)except Exception:break


运行结果:

 (二)

from collections.abc import Iterable
from collections.abc import Iteratorimport time
class Person(object):def __init__(self):self.names &＃61; list()self.current_num &＃61; 0def add_person(self,name):self.names.append(name)def __iter__(self):#passreturn PersonsIterator(self)class PersonsIterator(object):def __init__(self,obj):self.obj &＃61; objself.current_num &＃61; 0def __iter__(self):passdef __next__(self):#pass#return 12345if self.current_num p1.add_person(&＃39;张三&＃39;)
p1.add_person(&＃39;李四&＃39;)
p1.add_person(&＃39;王五&＃39;)print(isinstance(p1,Iterable)) #判断是否可以迭代
# iter()的作用是调用p1的iter()方法
# next()的作用是调用迭代器的next方法
p_Iterator &＃61; iter(p1)
print(isinstance(p_Iterator,Iterator)) #判断是否为迭代器for temp in p1:print(temp)time.sleep(1)

运行结果: