python学习笔记11-迭代器
- 迭代器定义的是一个迭代方法,迭代器本身不返回值,但可以通过next()方法逐一迭代调用,但更常见的是用for循环调用
s = 'xyz'
it = iter(s)
it
<str_iterator at 0x1d7f8017a20>
next(it)
'x'
next(it)
'y'
next(it)
'z'
next(it)
StopIteration
- 迭代器it生命周期结束,此时it也无法用for来调用
for char in it:
print(char)
- 需要重新对it赋值
it = iter(s)
for char in it:
print(char)
x
y
z
- 或者直接用iter(s)作为迭代器
for char in iter(s):
print(char)
x
y
z