python 模块

  编写一个进度条

1 #!/usr/bin/env python3
2 
3 import sys, time
4 for i in range(31):
5     sys.stdout.write('
')#每次固定在开头,清空原行
6     sys.stdout.write("%s\%% | %s" % (int(i / 30 * 100), int(i / 30 * 100) * "*"))#int(i / 30 * 100) * "*"代表打印多少个*
7     sys.stdout.flush()#强制刷新屏幕
8     time.sleep(0.3)#等待多少秒
 1 import sys,time
 2 for i in range(1,100):
 3     if i < 9:#判断是否是占两位数
 4         sys.stdout.write('#'+'%'+str(i+1)+"")#进度条退两格,为连接下一个#腾地方
 5         sys.stdout.flush()#刷新显示
 6         time.sleep(0.5)
 7     else:
 8         sys.stdout.write('#' + '%' + str(i + 1) + "")
 9         sys.stdout.flush()
10         time.sleep(0.5)
1 time.sleep(5)
2 print("wake up ....")
3 print(time.time())#时间戳1970 1 1到现在的过去多少秒
4 print(time.ctime())#返回当前时间
5 print(time.ctime(time.time()-86400))#将时间转换成字符串昨天的这个时间
6 time_obj=time.gmtime(time.time()-86400)
7 print(time_obj)
8 print("%d-%f-%s %s:%s" % (time_obj.tm_year,time_obj.tm_mon,time_obj.tm_mday,time_obj.tm_hour,time_obj.tm_min)) #格式化
9 # import sys
"""

wake up ....
1507429553.1381178
Sun Oct 8 10:25:53 2017
Sat Oct 7 10:25:53 2017
time.struct_time(tm_year=2017, tm_mon=10, tm_mday=7, tm_hour=2, tm_min=25, tm_sec=53, tm_wday=5, tm_yday=280, tm_isdst=0)
2017-10.000000-7 2:25

"""

 
1 import datetime
2 print(datetime.datetime.now())#返回当前系统时间
3 print(datetime.date.fromtimestamp(time.time()))#时间戳直接转成日期格式
4 print(datetime.datetime.now() + datetime.timedelta(3))#当前时间加三天
5 print(datetime.datetime.now() + datetime.timedelta(-3))#当前时间减三天
6 print(datetime.datetime.now() + datetime.timedelta(hours=3))#当前时间加3小时
7 print(datetime.datetime.now() + datetime.timedelta(minutes=30))#当前时间加30分钟
"""
运行结果

2017-10-08 11:11:59.362852
2017-10-08
2017-10-11 11:11:59.362852
2017-10-05 11:11:59.362852
2017-10-08 14:11:59.362852
2017-10-08 11:41:59.362852

"""

 

 sys模块

sys.path()其中有一个目录Python35\lib\site-packages将写好的py放入其中,import 就可以导入,一般import导入则在当前目录,如果想在任何地方都可以导入就放入site-packages中

sys.argv运行后面带的参数

1 import sys
2 print(sys.path)
3 print(sys.argv)
4 if sys.argv[1] == 'sleep':
5     print("hello")
6 else:
7     print("wakeup")
"""

H:python17w4>python timemodle.py sleep
['timemodle.py', 'sleep']
hello

H:python17w4>python timemodle.py sleep
['H:\python17\w4', 'C:\Python27\lib\site-packa
ges\paramiko-1.13.0-py2.7.egg', 'C:\Windows\syst
em32\python27.zip', 'C:\Python27\DLLs', 'C:\Pyt
hon27\lib', 'C:\Python27\lib\plat-win', 'C:\Py
thon27\lib\lib-tk', 'C:\Python27', 'C:\Python27
\lib\site-packages']
['timemodle.py', 'sleep']



 如果想安装django

在Scripts目录中找到pip.exe

在命令行中运行pip.ext install django

卸载pip.exe uninstall django

pickle模块

dumps

loads

初始化,写一个字典存起来

 1 #!/usr/bin/env python3
 2 import pickle
 3 account_dic={
 4     1000:{
 5         'name':"aric",
 6         'passwod':'123',
 7         'bank_acc':1234556,
 8         'balance':15000
 9     },
10 
11     1001: {
12         'name': "robert",
13         'passwod': '456',
14         'bank_acc': 334589,
15         'balance': 15000
16     },
17 
18 }
19 f=open('accout.db','wb')
20 f.write(pickle.dumps(account_dic))#与pickle.dumps(account_dic,f)相同
#
f.write(bytes(json.dumps(account_dic),encoding='utf-8'))#如果用json
21 f.close()

修改balance程序

 1 #!/usr/bin/env python3
 2 import pickle
 3 file_name='accout.db'
 4 f=open(file_name,'rb')
 5 account_dic=pickle.loads(f.read())
 6 f.close()
 7 account_dic[1000]['balance'] -=500
 8 print(account_dic)
 9 f1=open(file_name,'wb')
10 f1.write(pickle.dumps(account_dic))
11 f1.close()

查看之后数据修改的情况

1 #!/usr/bin/env python3
2 import pickle
3 f=open('accout.db','rb')
4 account_db = pickle.loads(f.read())#可用account_db=picle.load(f)
#
account_dic=json.loads(f.read().decode("utf-8"))如果用json

5 print(account_db)

 json将字典写入文件中

1 import json
2 data={101:101,102:"cat"}
3 f=open('db','w',encoding='utf-8')
4 json.dump(data,f)
5 f.close()

读文件

 1 #!/usr/bin/env python3
 2 import json
 3 # data={101:101,102:"cat"}
 4 # f=open('db','w',encoding='utf-8')
 5 # json.dump(data,f)
 6 # f.close()
 7 f=open('db','r',encoding='utf-8')
 8 #n=json.loads(f.read())
 9 n=json.load(f)
10 print(n)
11 f.close()
原文地址:https://www.cnblogs.com/wang43125471/p/7636752.html