# for temp in [11, 22, 33]:
# print(temp)
# for temp in "abcdef":
# print(temp)
# for temp in 100:
# print(temp)
# from collections import Iterable
# print(isinstance([11, 22, 33], Iterable))
# print(isinstance((11, 22, 33), Iterable))
# print(isinstance("abc", Iterable))
# print(isinstance(100, Iterable))
# a = 0
# b = 1
# print(a)
# a, b = b, a+b # (1, 0+1)
# print(a)
# a, b = b, a+b # (1, 0+1)
# print(a)
# a, b = b, a+b # (1, 0+1)
# print(a)
# a = (11, 22, 33)
# print(list(a))
# nums = [x*2 for x in range(10)]
# print(nums)
# nums = (x*2 for x in range(10))
# print(nums)
# for num in nums:
# print(num)
# import urllib.request
# req = urllib.request.urlopen("http://www.baidu.com")
# content = req.read()
# print(content)
# Python2适用
# import MySQLdb
# Python3适用
# import pymysql
# from pymysql import connect
# # 创建Connection连接
# conn = connect(host='localhost',port=3306,database='jing_dong',user='root',password='123456',charset='utf8')
# # 获得Cursor对象
# cursor = conn.cursor()
# count = cursor.execute("select * from goods;")
# print("查询到%d条数据" % count)
# # print(cursor.fetchone());
# # print(cursor.fetchone());
# # print(cursor.fetchone());
# # print(cursor.fetchone());
# # print(cursor.fetchmany());
# # print(cursor.fetchmany(3));
# # print(cursor.fetchall());
# # print(cursor.fetchall());
# # line_content = cursor.fetchone();
# # print(line_content)
# # print(line_content[0])
# # print(line_content[1])
# # print(line_content[2])
# # for temp in line_content:
# # print(temp)
# lines = cursor.fetchmany(5);
# for temp in lines:
# print(temp)
# # 关闭Cursor对象
# cursor.close()
# conn.close()
# # print(cursor.fetchone(), "---->");
# # count = cursor.execute("select * from goods;")
# from pymysql import connect
# # 创建Connection连接
# conn = connect(host='localhost',port=3306,database='jing_dong',user='root',password='123456',charset='utf8')
# # 获得Cursor对象
# cs1 = conn.cursor()
# # print(cs1.execute("""insert into goods_cates (name) values ("硬盘")"""))
# # print(cs1.execute("""insert into goods_cates (name) values ("硬盘2")"""))
# # print(cs1.execute("""insert into goods_cates (name) values ("硬盘3")"""))
# # conn.commit()
# print(cs1.execute("""insert into goods_cates (name) values ("硬盘3")"""))
# print(cs1.execute("""insert into goods_cates (name) values ("硬盘4")"""))
# conn.rollback()
# print(cs1.execute("""insert into goods_cates (name) values ("硬盘4")"""))
# conn.commit()
# import urllib.parse
#
# print(urllib.parse.quote("@"))
# print(urllib.parse.quote("中国"))
#
# print(urllib.parse.unquote("%E4%B8%AD%E5%9B%BD"))
import time
from collectionsimport Iterable
from collectionsimport Iterator
class Classmate(object):
def __init__(self):
self.names = list()
self.current_num =0
def add(self, name):
self.names.append(name)
def __iter__(self):
"""如果想要一个对象成为一个可以迭代的对象（即可以使用for），那么必须实现__iter__方法"""
# return ClassIterator(self)
return self
def __next__(self):
if self.current_num < len(self.names):
ret =self.names[self.current_num]
self.current_num +=1
return ret
else:
raise StopIteration
# class ClassIterator(object):
# def __init__(self, obj):
# self.obj = obj
# self.current_num = 0
# def __next__(self):
# if self.current_num < len(self.obj.names):
# ret = self.obj.names[self.current_num]
# self.current_num += 1
# return ret
# else:
# raise StopIteration
classmate = Classmate()
classmate.add("宏杰")
classmate.add("永振")
classmate.add("明越")
# print("判断classmate是否是可以迭代的对象：", isinstance(classmate, Iterable))
# classmate_iterator = iter(classmate)
# print("判断classmate_iterator是否是迭代器：", isinstance(classmate_iterator, Iterator))
# print(next(classmate_iterator))
for namein classmate:
print(name)
time.sleep(1)
"""
nums = list()
a = 0
b = 1
i = 0
while i < 10:
nums.append(a)
a, b = b, a+b
i += 1
for num in nums:
print(num)
"""
class Fibonacci(object):
def __init__(self, all_num):
self.all_num = all_num
self.current_num =0
self.a =0
self.b =1
def __iter__(self):
return self
def __next__(self):
if self.current_num
ret =self.a
self.a, self.b =self.b, self.a+self.b
self.current_num +=1
return ret
else:
raise StopIteration
fibo = Fibonacci(10)
for numin fibo:
print(num)
def create_num(all_num):
print("---1---")
# a = 0
# b = 1
a, b =0, 1
current_num =0
while current_num < all_num:
print("---2---")
# print(a)
yield a# 如果一个函数中有yield语句，那么这个就不再是函数，而是一个生成器的模板
print("---3---")
a, b = b, a+b
current_num +=1
print("---4---")
# 如果在调用create_num的时候，发现这个函数中有yield，那么此时不是调用函数，而是创建一个生成器对象
obj = create_num(10)
obj2 = create_num(2)
ret = next(obj)
print("obj:", ret)
ret = next(obj)
print("obj:", ret)
ret = next(obj2)
print("obj2:", ret)
ret = next(obj)
print("obj:", ret)
ret = next(obj)
print("obj:", ret)
ret = next(obj)
print("obj:", ret)
ret = next(obj2)
print("obj2:", ret)
ret = next(obj2)
print("obj2:", ret)
# for num in obj:
# print(num)
def create_num(all_num):
# a = 0
# b = 1
a, b =0, 1
current_num =0
while current_num < all_num:
# print(a)
yield a# 如果一个函数中有yield语句，那么这个就不再是函数，而是一个生成器的模板
a, b = b, a+b
current_num +=1
return "ok~~~"
# 如果在调用create_num的时候，发现这个函数中有yield，那么此时不是调用函数，而是创建一个生成器对象
obj2 = create_num(20)
while True:
try:
ret = next(obj2)
print(ret)
except Exceptionas ret:
print(ret.value)
break
def create_num(all_num):
a, b =0, 1
current_num =0
while current_num < all_num:
ret =yield a
print(">>>ret>>>", ret)
a, b = b, a+b
current_num +=1
obj = create_num(10)
obj.send(None)
ret = next(obj)
print(ret)
ret = obj.send("hahaha")
print(ret)
import time
def task_1():
while True:
print("---1---")
time.sleep(0.1)
yield
def task_2():
while True:
print("---2---")
time.sleep(0.1)
yield
def main():
# 此时并非函数调用，而是创建生成器
t1 = task_1()
t2 = task_2()
# 先让t1运行一会儿，当t1中遇到yield的时候，再返回到这里
# 然后执行t2，当它遇到yield的时候，再次切换到t1中
# 这样t1/t2/t1/t2的交替运行，最终实现了多任务……协程
while True:
next(t1)# 调用task_1，yield时返回
next(t2)# 调用task_2，yield时返回
if __name__ =="__main__":
main()