1 import sys
2
3 print(sys.path) #新建文件名不能与导入的模块名相同
4 print(sys.argv)

1 import os
2
3 cmd_res = os.system("dir")#执行命令，不保存结果
4 cmd_res = os.popen("dir").read()
5 print("-->",cmd_res)
6
7 os.mkdir("new_dir")#新建目录

 1 import getpass
 2
 3 _username = 'Irlo'
 4 _password = 'abc123'
 5 username = input("username:")
 6 password = getpass.getpass("password:")  #pycharm中getpass不可用
 7
 8 if _username == username and _password == password:
 9     print("Welcome user {name} login...".format(name=username))
10 else:
11     print("Invalid username or password!")

name = "Irlo"print("My name is %s" % name)#输出"My name is Irlo

 1 name = "My name is Irlo"
 2
 3 print(name.capitalize())
 4 print(name.count("m"))
 5 print(name.center(50,"-"))
 6 print(name.endswith("lo"))
 7 print(name.find("s"))
 8 print(name.format(name="Irlo",year=26))
 9 print(name.isalnum())
10 print("234".isdecimal())#判断是否为十进制
11 print("1A".isdigit())#判断是否为数字
12 print("1A".isidentifier())#判断是否为一个合法的标识符
13 print("33.2".isnumeric())#判断是否只有数字
14 print("My Name Is   ".istitle())#判断是否是标题，如果首字母都是大写就算是
15 print("+".join(["1","2","3"]))#把列表按照适当的方式变成字符串
16 print(name.ljust(50,"*"))
17 print("Irlo/n".lstrip())#strip会去除两边的空格和回车，lstrip会去除左边的空格和回车
18 print(name.maketrans())

str operation

1 name = ["Irlo","Xiaoxiao","Dali"]
2
3 name_list = list(["Irlo","Xiaoxiao","Dali"])

 1 names = ["ChenXiaojie","JiYuchi","YuTao","XiaoXiao","LiYuhan"]
 2 names2 = ["1","2","3","4","5","6"]
 3 #print(names[2])#切片
 4 #print(names[-1])#切片
 5 #print(names[:3])#切片
 6 #print(names[-3:])#切片
 7 names.append("KangKai")#添加
 8 names.insert(1,"DengKai")#插入
 9 names.insert(3,"XiaoXiao")#插入
10 names.remove("YuTao")#移除
11 del names [0]#删除数据
12 #print(names.count("XiaoXiao"))#计数
13 #print(names.index("JiYuchi"))#获取下标
14 names.reverse()#倒转顺序
15 #del names2  #删除变量
16 names.extend(names2)#扩展
17 names.sort()#排序
18 print(names)

 1 import copy#完全复制需要导入模块copy
 2 names = ["JiYuchi","YuTao",["XiaoXiao","LiuSijia"],"DengKai","ChenXiaojie"]
 3 name2 = copy.deepcopy(names) #深copy(完全复制)尽量不用，因为会占用很大的内存
 4 names[1] = "于涛"
 5 names[2][0] = "XIAOXIAO"
 6 print(names)
 7 print(name2)
 8
 9 names = ["JiYuchi","YuTao",["XiaoXiao","LiuSijia"],"DengKai","ChenXiaojie"]
10 name1 = names.copy()#浅copy，只copy第一层
11 names[1] = "于涛"
12 names[2][0] = "XIAOXIAO"
13 print(names)
14 print(name1)
15 names = ["JiYuchi","YuTao",["XiaoXiao","LiuSijia"],"DengKai","ChenXiaojie"]
16 for i in names:
17     print(i)
18 #range(1:10:2)
19 print(names[0:-1:2])#选中范围头和尾，步长为2，打印偶数的人名
20 print(names[::2])#当0和-1时可以省略
21 print(names[:])#表示从头全部打印

copy

info = {"snis1701":'mingrihua',"snis1702":'tongxuehui',"snis1703":'heidaodage',"snis1704":'guanggao',
}

 1 info = {
 2     "snis1701":'mingrihua',
 3     "snis1702":'tongxuehui',
 4     "snis1703":'heidaodage',
 5     "snis1704":'guanggao',
 6 }
 7 print(info) #字典是无序的，它没有下标
 8 #print(info["snis1701"])#取出，用这种方式查找如果字典中不存在的话会报错，不推荐
 9 info["snis1701"] = "明日花"#修改
10 info["snis1705"] = "shuicaili"# 如果原字典中没有则添加
11 del info["snis1701"] #python自带的删除方式
12 info.pop("snis1702") #字典的删除方式
13 print(info)
14 print(info.get("snis1706"))#字典中常用的取出、查询方式
15 print("snis1703" in info) #判断字典中是否有这一项；在python 2.x中写作info.has_key("1703")

 1 game_catalog = {
 2     "Europe and American":{
 3         "BlizzCon":["WOW","Diablo","OverWatch"],
 4         "Ubisoft":["Assassin","Rainbow Six","Tom Clancy's Ghost Recon"],
 5         "Frontier Development":["Elite Dangerous","Planet Coaster","Screamride"],
 6     },
 7     "Japan":{
 8         "Capcom":["Resident Evil","Street Fighter","Asura's Wrath"],
 9         "Square Enix":["Final Fantasy","Dragon Quest","NieR Automata"],
10         "Namco":["Pac-Man","Ace Combat","Tekken"],
11     },
12     "China":{
13         "Tencent":["LOL","King of Glory","CrossFire"],
14         "Netease Games":["HearthStone","Heroes of the Storm","StarCraft"],
15     }
16 }
17
18 '''
19 game_catalog["China"]["Tencent"][2] = "Alliance of Valiant Arms"
20
21 game_catalog.setdefault("Korea",{                        #setdefult会看你新建字典的key是否已经在原字典中，如果原字典中没有，那么就把新字典加入进去；如果原字典中已经有了，那么就默认原字典的key不变
22     "Nasdaq Game":["Mir2","Aion","XCB"],
23     "Nexon":["Crazyracing","DNF","Counter-Strike Online"],
24 })
25 '''
26 add = {
27     "Korea":{
28         "Nasdaq Game":["Mir2","Aion","XCB"],
29         "Nexon":["Crazyracing","DNF","Counter-Strike Online"],
30     }
31 }
32 game_catalog.update(add)   #uodate用于更新字典，如果原字典中没有，则新添加进去；如果原字典中已经有了新字典中的key，则更新以新字典内容为准
33 print(game_catalog)
34
35 print(game_catalog.items())   #把字典变为列表

info = {"snis1701": 'mingrihua',"snis1702": 'tongxuehui',"snis1703": 'heidaodage',"snis1704": 'guanggao',
}
b = {"snis1701":"Book",1:3,4:9,
}
info.update(b)
print(info)
c = dict.fromkeys([5,6,7],[2,{"ubisoft":"Rainbow Six"},"Telsa"])#初始化一个新字典(初始化与原字典无关，所以用dict)，前面是key，后面是value
print(c)
c[7][1]["ubisoft"] = "Assassin"  #如果要修改，注意key要完全一致，不然会变成添加
print(c) #用fromkey创建字典只能创建一层，多层的话在修改的时候只能修改一层for i in info:print(i,info[i])

1 a,b,c = 1,2,3
2
3 d = a if a>b else c
4 print(d)

1 #str和bytes通过编码和解码的方式互相转换
2 print("哈哈哈哈".encode("utf-8"))# str转bytes的时候要说明str的编码方式，b表示bytes
3 b'\xe5\x93\x88\xe5\x93\x88\xe5\x93\x88\xe5\x93\x88\xe5\x93\x88'
4 print(b"\xe5\x93\x88\xe5\x93\x88\xe5\x93\x88\xe5\x93\x88\xe5\x93\x88".decode("utf-8"))#bytes转str的时候要声明转换成str时用什么编码