python基础深入(元组、字符串、列表、字典)

python基础深入(元组、字符串、列表、字典)

一、列表

1.追加

 >>>list = [1,2,3,4] #用于在列表末尾添加新的对象，只能单个添加，该方法无返回值，但是会修改原来的列表。
 >>>list.append(5)
 >>>print(list)
 [1, 2, 3, 4, 5]

2.统计

 >>>list = [1,"a","b","c",1,4,2,1,2,3,4]
 >>>list.count(4) #用于统计某个元素在列表中出现的次数，value -- 列表中统计的对象，返回元素在列表中出现的次数。
 >>>print(list)
 [1, 'a', 'b', 'c', 1, 4, 2, 1, 2, 3, 4]
 >>>print(list.count(4))#列表中4出现了两次
 2

3、合并

 >>>list = [1,"a","b","c",1,4,2,1,2,3,4]
 >>>list2 = ["aa","bb","cc"]
 >>>list.extend(list2) #用于在列表末尾一次性追加另一个序列中的多个值（用新列表扩展原来的列表），seq -- 元素列表，该方法没有返回值，但会在已存在的列表中添加新的列表内容
 >>>print(list)
 [1, 'a', 'b', 'c', 1, 4, 2, 1, 2, 3, 4, 'aa', 'bb', 'cc']

4、索引

 >>>list = [1,"a","b","c",1,4,2,1,2,3,4]
 >>>list.index(4)  #用于从列表中找出某个值第一个匹配项的索引位置
 >>>print(list.index(4)) #第一个4的指标是5
4 5

5、指定插入

 >>>list = [1,2,3,4]
 >>>list.insert(1,"a") #用于将指定对象插入列表,需要指定插入对象的位置
 >>>print(list)
 [1, 'a', 2, 3, 4]

6、删除最后一个元素

 >>>list = [1,2,3,4,"a"]
 >>>list.pop() #pop默认删除最后一个元素，a被删除
 >>>print(list)
4 [1,2,3,4]

7、指定删除

 list = [1,2,3,4,"a"]
 list.remove("a")  #指定删除，指定要删除元素的名字
 print(list)
 [1, 2, 3, 4]

8、多个删除

 list = [1,2,3,4,"a"]
 del list[2:4] #顾首不顾未可以删除连续的元素，删除3,4
 print(list)
 [1, 2, 'a']

9、步长

list = [1,2,3,4,"a"]
del list[::2] #步长为二，各一个打印一个
print(list)
[2, 4]

二、元组

元组不可修改删除，只有索引(index)和统计(count)可用

aaarticlea/png;base64,iVBORw0KGgoAAAANSUhEUgAAAjIAAABlCAIAAADYup5oAAAABmJLR0QA/wD/AP+gvaeTAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAVfElEQVR4nO3dfVBU570H8O8DuryIUORFIqxSry5ItnCnJC3Gi1Fi77TYGTpN6M3U2qkzFnJ7HXulvbnNH1bT/JEZ20BrnBRMZtKJk05uMJlhbiTOjeIL18rU2CpseL+yykKUBUVE0NXd5/5xdmGB3WV32ZcDfD+z45w9+5znPAd3n98+z/ntOWJ4eBiA0WjMy8sDERFRWEW4e6Grq8tisQCwWCwtLS1+L4fmMIiIaGFwG5bWrFljNBrv3btnNBozMzP9Xg7hsRAR0by3xN0LGo0mMzOzo6MjKytLo9FERUX5txzKgyEiovlOuD231BfkPacHuX4iIpqH3E7iERERhR7DEhERqQjDEhERqQjDEhERqQjDEhERqYjbBPF5q758Y8d/XNy3LtztCIy2j8SHBvuy1J84+Hyxn1t1V238bdbFGq82JyIKH/ejJdldVSJEhhAZ5fXS1UslVd3S9abh0121sa5kwcQkmKvOtkw8KfsX72KS663W7btYUrexqjvALSQiCjD3YUms21cnZe+JshC2Zo7qy3fi2PQBQX056r3cvhsbBYTjMftWvpZ3Uu5N+bbzFQOiIDUVQMHWn9Vs8K5qt1sV1xzDznKfmklEFGp+nVtSIlbdvnXCh426366aPuoKrPry7djvPFCqL4cQ2H7U2wqqDuGYhFQeJ7B9IzyPLXwt79wwLxplrjrbAv3WH+AW9D+4uDnFu7o9brVu335sZ2AiIjWb7SoPsr5cW1fSW1PsSwRyYWY9gb7KQ325qCuRM0+elAuUSHgz/TWt5Kwb+lpe0V2F9R+ioAn7vWtVgLn7MxERqYPvoyUP55waykWGsD8mzjwp5bXbj+Lodq2rraaoLxczefP9vr7uaFnJ3DrbGuc40Y3mAui8Ll+1ETjhRZjpxs4P0XURuXNoJwC0fSRefdX+OPjHKrPXGxaXlB2t43iJiFTL97Dk7pyTrC//cXNlo5QmKXu7KtHeOb182YleKU2eB17FNXKmMHy3r/8tfnAM3qROlAsIARyDN60s34ljF72q1qO28v9qgdSfOHBA/mxrAW592OZ9XCIiUrUA/m5Jl53f1N4DQAlFc573C5/6ctSVwMt8vhoJKYGd2Fg1e7UlAYhJADbUHDwoDz5fDHPV8YYmMW//0EREMwQuLIl1++pkycmpM3g+83sSL2CTU1UbUVfi1dDH2b6LyK2YJbmu7ii2O9L2jgLbxeyRzC37JN5bFVhZIH35WwdgspOIKIgCfJWH4kNSmqT8PXZ+z7/I5P8kXkDiUrnTdFx31Sxhxqskbyc1E2l7EmXACYmL+/xrprnqbAtkauXPDsh/3eLTaSpGJSJSucCFJVlf/rJTL33ZcW7JTped39xhBID6t4PzO9zimhN4zYvfi9aXCyFc/bC0vhwlcnLu7r/blJQHt+WzfzqZE9FdhaNlSsqD2/K+tse9wfZbjkWzudn77bqrXsMJZuERkaoNDw8PDw9fuXJl+hClt6sy36lcfmVXryOdwYv1Ze9JaZr6eK9syktBcaIMZScmn0jA8SibWsqp2IQyOJV33sRNedklC3yp375R5eQu7IU8lnddybm3cPAgDh7EgbcK3jqAgwfx1rmuWTaa8schIlKnhXd3Wm+uiVdfXo4aH0YNaivvB14Tj4jmh4V3qdbimoue+17lunk1XleotvL+Wbcv6LsgIgoAt+eWum53WawWABarpcXcEvDlUBycy+Pqkv927s1iwGKxtLS0WCwWAMq/86I8EdHCFvmrX/0KwPDwcFpamvMLyx8uN941aiI1pnsmbbzWdM8U2OWklUlhOeDly5cbjUaNRmMymbRarclkUpaTkly3R23liYgWNk/nlixWS8ftjqwVWZpITeCXV2vCc8SAxWLp6OjIysrSaDTOy/OlPBHRAiakpRfA1dahvJwpX8/7BjKCuuP0VJPrBmm0AJRWERHRYsObphMRkYowLBERkYowLBERkYowLBERkYowLBERkYowLBERkYq4DUtSdr9dIjIyREZGeYN09VJJVU8wLgRORESLmNuwJMS6n9bJ3t4TPwxlc4iIaHHzZxJPiVimun1f9eVu3T1vVzVwdEVERB6F6NySlPV/fLU9NPsiIqL5y+ew5OmcU0N5RoawPxxnnpTyWu32P+Poj7UutiIiIprgc1hyd85Jyvr//HHzgUZpMsne3q4DaO+ZXr7svV5pMtUU+TL1R0REi0oAbwOoW5/f1NUDfFUJRbzpHBER+Sxg55aUUdG3T06ZwSMiIvJJgFMeig5Jk0n2/h7//j1GJiIi8lnAwpKU9S+/XD/5/LL93JKDbn1+8/8ZAaDh7aoeCUhjVaFWFL7dLRm+iIjIbparPExm0LnLrJucr9Ot79iupOFpCyuy3puS2iDEut0/z321UGRkiJP/4NsPnoiIaPHg3WmJiEhFeKlWIiJSEYYlIiJSEYYlIiJSEYYlIiJSETE8PAzAaDTm5eUFpMZz584FpB4iIlI8++yz4W5C6ATw4kOTjONRwaiWiGgh+ee8NQkJCbMWu3TpUggaox5BCUtEROQ9g8Hgcr1erw9xS9SAYYmIKJwMBkNWVtZjVwwGwyKMTEx5ICIiFWFYIiIiFQnRJF5spHhSY020WTQCACwStyM0rZbIMat6r9Mq0dvRcHd1kT423C2ZjyRGTA0tMUWbksPdEiKaX0IRltZHQyfvR8Utj4xJEEIAiJEybnxs5b17nUtjux5MLy8xYmr4qAtPF/gYEiR6O2pP9UOXWzrX3lBixNRwI7lokx8xyd7+IcBNS+So4fKnl0aAVYW7stPm1tC58ftP7UVt8RlFqzsaDLGM67QQzfoxJ78FfRJvfTSyxXhsSuqSmFgBQEpIKYAlMbGxyanZYnx9dMD2JaDNKt22KhBVDV0+j2/4+VYTiNcW7drqpiUSI6a/Xoor3LW1dBsaLwzOqZmqJqDN+gZaL/Oqu7QAef6Y01wEd7QUGwmdbTQ6JVUIYMZ9lYRA9IoknXmgLzJuzOq0HvHaol3aoLbMI3nzQjPyiuKCVP3d+0O65DQIaLNLw3iUQKD/1DNrE3H6TLzbfjPMg0KimcY6DWM6PUc5KhTc0VLOksdRcXFCANLm8iEEouLinlz6OKjN8NVQX+eq9DAHjAUjKV3X38cBE6mLRO+Nq3fD3QpyLbijpRXWB5FRyZDyC9OXf79uv8FSrja9ubdPWchdvSoyKjpxZBCwj01cztg6nTRaPVh7qh8AEJ/3/FO6eGWrsc5Pmq6aAcTnPe08yJlYj7XbivK1TlUBa7dtTb9xprFz2tSwRO/gNV1y/pQDkTcvnGnstD9JmnImZuYu3HE6NPTXTt+v92Y9BK/rCfDk+ODld5uvzagtbfWqxhuD+Vp+LSU1cPkxTLKvtL915cTTF/TjZz7uGtLlfifB+OmlEUz/+LvjfbdAMwU3LGmkVUDCJpUZvB9tzO8x377Q3TOxkJuRJgCNbXK0pEwEZaC3o/aG00ptVuk21J5qrkVu6a5se9ZAy6BuUzIw1vlJKzYXlcZDeTcgUekBp63/vDPhKV28gDar9PllDeeRpUVcwvq1CUn5s7zJJHo7Gu+s/84ubZw9wWwMiHW/C3f1OB9a8hzCgB+HMGt7/G3LFMn5u7bmB6w2omBw8zGMzyjadt/x1hUTT0VCRtG2+7Wnmv/6dEHprlilh7mc4DnS+NQt0ExBTnmwyQlQ/sX0BSmlhJc3UXf6Gh6XoIyKJEaGTImZjv/1GF3eKjfr40w3xgAo77lvZN769IKpswVZ3nToCcuSzPdH7dtqiybGcG53EWy+HwIR+U2X6xghxejyVl274SFTKYzdwoIR3NGSRYgYqxVCABIAbDZ74sPUhUdz+vHS3ftDiHG9vrOrttNpjS7ZMcoRcfqcvE+a7rnIaxDQJq89NXhzU3LaxJp4bdGuwcvvNjROG8J72kWweTgEdbl5o3/t6uxwt4IoVMLZLSwMwQ1LQxHRcePjkTExsEnAnh0+bcE6Pn47Mhr+Jz0kLEtyt16X6+bnnHLUcB2bC5afb7+pnZkklpSua+7rzU6bMk5Pzt9VlA85arjcYMixRyZPuwg2z4egHkN9navSN4W7FUQBMnp3NClhtacS4ewWFobgTuK12aIejIzAan0yLWXHU7mw2TITE6YsWK0PRkZabf7fCEMgPinjzuBN+9Ohy/aECGW9sXNEWS/R295gGLMvj5g6sEYXH6PbvKzVxS+HRNqmXFztHcXkts4/vhm6OzEZ6G4XPpHoba99t8GXbV0egh/1BKo9bqsaNRixTc1RkxarhGVJd8ZHAWCwc+Kt3qn0JBIjpgZ7T6Ksb3b0AOP9RmSs9jD0CVS3sJgFd7Q0ZkOX5ivZQ0PRiYmImBECbbYHd+50ab4y5jRUmp4nk/R0QZE+xpF71t+QUFCkj3G8afprkVu6KVn33WRlhg1YVbht1bVTzQ0JBUX6WN13czo/aag1A1DOS8VOprGlIEuf1H++a8gMpZKpTUvKz+uovTBoX5+w7O5HDbX2l1YV7poo7GYXLg5hIkVCyc9xzsQT0GYV6vob7455N9J3fwi+1uO6nb62x1M7P72bWbrorn9M6icQn5GTeObTd7uUi60AgDarUHem8d1+AEhZ/51tqz491dyQ8M2tCYAuN/1GQ+0pQMmsi4fHj7nLboG8F5S70067DeD6JY/WPxyOjlsWGRWNCAEANml9+ODB6P2uqMSuxyq9uUYor4kn0dtxGdlzTiQNSz3SKalprPOTJlOm46sDr4lH856cc+qsB8ptAD3c2OL+/ft6vf7SpUu8O22AdT1e2rckOccyvmL0jkZaIcRDRN7WxLQtSR577GUOXhgIaLOLQvGDg4nr783TepQkkWblHO/kd8Z47ZxbQhRectrETLjbs0iEaKQyJsXn1lhEOg08rO5LLzIiQD14GOtR8kGIFpiwXwhtceL9loiISEUYloiISEUYloiISEUYloiISEUYloiISEWCkom3vfCbwaiWiGgheTRyc/ZCiw9HS0REpCIMS0REpCIMS0REpCIMS0REpCIhCkvikSXC2BFx5S8Rn5+L+PxcxJWLEdc7xSNLaPbuHwlDbeVpD7ehVBWJgfOV77eFuxlERHMUimviRQx+ieudS5cti0z8ihACgJTSOj7yqPmiWKOzJT8Rgjb4SmKgsfKqvmKHHxdnlBhorPx1nRFA4e7DOzbMLGA+/eZrtdeBgpeqS3Pm3FYAgEBqYUXe8crTKRXP8YKSRME268ec/Bb00VLEYL8wdkSvSF4SE6tEJEgpgCUxsdErkoWxI2Kwf9ZKQq/9gz9hp59vNYHUzRXVvzu8p8DVqxIDjcdqn3ip+neH96A6kOMbAf0LO/HnDwyBq5KIXPP8Mae5CG5YEpaH6OmIWpEkhONG6U4PIRC1Igk9HcLyMKjNcGnw7Gl3IUG2vv8OijenBGnPA7eMhfocCOhLA/0lS6Q89y0cqW0NaKVEC5GHHoDCK8hhqa9naWysEIC0uXwIgaWxsaLvWlCbMZOE4czHbn/I1t7cWJA7X++pmp1b2NTMARORJ557AAqvIJ9bum2OTIiHlF+Yvvz7dZOyLleb3tzbpyzkrl4VGRX96PYAvjpl2CBb3/9ldaOy7HwCZmL9mu//Zu+WVMf0rn1ud/LpH/IMPz/ShMLdh/MMe480ATM2AYCmvY0z54UlDIa/FOpfnHIczu1BZukrTudvBs8eev3jawDwzJ43XvQUzGbdtZckDMeVg3pmz+9yr/6yempVOXkF1VfbXtRzsptoJpcfw2y3Pcm3zFW/rjMW7t6f9tlrtdcx/ePvjvfdAs0U5LBkeSCwHDYJKQH8aGN+j/n2he6eiYXcjDQB4OGUSbzBs4de/zh99+Fqx/vj/bacHRuU2HAy7ZXD1clA2wcv1bZWl+akFlbsubX3qrKhgOOp0L9weA/2HnlnL3Yfri61Zxl81rZlxwakbq6oLoTh+N6reu+igoTheHVfyf7qzSlKez4zA8mOpv4ZP3njcKqyfPhs6t4tqe7qEb7v2k09+hcO/2Zl5Z/wnB4pqSXPpOW8yDQHIq+4+Ri660mUhSPvHCtVep7Bs4de/2Cl50jjU7dAMwU55UFOUpaB6QtSSojJW6dLDLT+DSX77W8XgdTNFY7vLyf7Snba+9/s50q/PDlr9rbTGCJl5RwS/lJXZl67ZZ7SHkdT07/leMMlbSl+4m8toUkoF0gt3Jl/5bX3G8/+D55jTCIKqsLdjhFS0pbigr9c9XBSKozdwoIR5NHSUg2sVggBSACw2ZRh0/SFSOdmDNwyputdpBtMXZ+y8gnjVTOQFOgmC+j1zxwxtO7YkDOxJnVzRXXbBy/9onraEH7glrGxbm+j09aFesdAKthEynM//P6h128Wv7Fl6gutV5ueySsNSRuIaIZwdgsLQ3DDkkxMsd67HRkTA5sEHMl4Uxes4+My0TkKpa7M7DObscGxTpoHhlJSk6atN9/6MjNta3CanZ1b+E6zoTRnyjh9w4vVb7wIaT79ZuXpH9ojU+rKzMLdFeH5yYI0n27AT15J+1Ntq975x0/tzY0FuTvC0SKiRWD2niec3cLCEORJvNXrLKOjsFqfTEvZ8VQubLbMxIQpC1arZXQUa9ZPbCGQmvN11J2255JJ8+k3Tw8kK9NW306fWN9+uhZf/5rjC0ijoRWwn4iyJzjMxh7kALSdnT4ZKHJ27Eb9ebP9qYSh1vnHQMab5smm9n12dmCymF9XhZAw1O596Re+bCsx0HgaRVtSk7b8ZOXJyR8/SfPpz7AnUD/RJVq4XPYA7nqSxnccPcDQF5edeh4XAtUtLGZieHgYgNFozMvLC0iN586de/KpzRNPI27eQKchOjERETNCoM324M4d6PS2tNXTXpnMY3GT9uYyPQ9YW7K/+NZrR5oy/+kfjf97xbF5kqvfY09s5fJSC9LpjKhz6s7M8pNNxbQ0HkcJp0NwKjyzMfAyMc+Ribe2ZP/LOV8oFSrZRHNNpiBaPGb2AK56ktJX9q088/Or+pfwjvKSI7POw8ccrroFlx6N3ExISDAYDFlZWY9duX//vl6vv3Tp0rPPPhuMP4I6BT0sAYi4eUN2tmhiYyOjohEhAMAmrQ8fWMbGhO5rM2OSSkgYjlfe2hqSa/lIGI5/gNI5JJIqKYIpnDogCigZzG97DEsuheKaeLa01WLFSktPO4YGhOUhhIAmSialIvcZmyYqBA3wj4C+tCIUPziYuP7eXCpRUgQD1SQigtNsXtNebyczaO5CEZYASE0UsvJgT8ijKRhRiNRJycLdPHtBCiTeb4mIiFSEYYmIiFSEYYmIiFSEYYmIiFSEYYmIiFTk/wGhJ7ln2LPvfwAAAABJRU5ErkJggg==" alt="" />

三、字符串

1、首字母大写

 >>>name="zhangkui,zhangruzhan"
 >>>print(name.capitalize())#只有字符串第一个字母大写
 Zhangkui,zhangruzhan

2、内容居中

 >>>name="zhangkui,zhangruzhan"
 >>>print(name.center(40,'*'))
 **********zhangkui,zhangruzhan**********

3、统计

 name="zhangkui,zhangruzhan"
 print(name.count('a')) #统计字符串中a出现的次数
 3

4、编码修改

 name="zhangkui,奎"
 print(name.encode('gbk')) #编码，针对unicode  encoding='解码的格式'
 b'zhangkui,\xbf\xfc'

5、判断是否以xxx结束

 endswith(self, suffix, start=None, end=None)是否以xxx结尾 suffix：填入结尾的字符串  start=在第几个字符开始  end=在第几个字符结束
 endswith() 方法用于判断字符串是否以指定后缀结尾，如果以指定后缀结尾返回True，否则返回False。可选参数"start"与"end"为检索字符串的开始与结束位置。
 例：
 >>> name='asdfghjklo'
 >>> print (name.endswith('lo',0,6))
 False
 >>>name="ruzhan"
8 >>>print(name.endswith('zhan',2,))
9 Ture

6、find

 find(self, sub, start=None, end=None)寻找子序列位置，如果没找到，返回 -1
 >>> name = 'yaotwosiji'
 >>> print (name.find('two',1,8))
 3
 >>> print (name.find('two',1,3))
 -1

7、大写转小写

 >>>name="AVXS"
 >>>print(name.casefold())
 avxs

8、索引

 name="zhangkui,zhangruzhan"
 print(name.index('ru'))
 14

9、isalnum 判断字符串是不是有字母数字组成，是返回Ture否则返回False

 >>>name="zhangkui,zhangruzhan"
 >>>print(name.isalnum())
 False

10、isalpha 如果字符串至少有一个字符并且所有字符都是字母则返回 True,否则返回 False

 >>>name="zhangkuizhangruzhan"
 >>>print(name.isalpha())
 True

11、isdigit  如果字符串至少有一个字符并且所有字符都是数字则返回 True,否则返回 False

 >>>name=""
 >>>print(name.isdigit())
 Ture

12、islower 所有字符不包含大写字母返回True，否则返回False

 >>>name= 'a, dsbc'
 >>>print(name.islower())
 True

13、isspace 只包含空格返回True否则返回False

 >>>name= ' '
 >>>print(name.isspace())
 True

14、istitle

 istitle(self)如果字符串中所有的单词拼写首字母是否为大写，且其他字母为小写则返回 True，否则返回 False
 例：
 >>> zifu = 'Liu Yao'
 >>> print (zifu.istitle())
 True

15、isupper

 isupper(self)如果字符串中包含至少一个区分大小写的字符，并且所有这些(区分大小写的)字符都是大写，则返回 True，否则返回 False
 例：
 >>> zifu = 'LIU YAO'
 >>> print (zifu.isupper())

16、join

 join(self, iterable)返回通过指定字符连接序列中元素后生成的新字符串
 例：
 >>> lj = '^'
 >>> name =('y','a','o')
 >>> print (lj.join(name))
 y^a^o

17、l just

ljust(self, width, fillchar=None)返回一个原字符串左对齐,并使用空格填充至指定长度的新字符串。如果指定的长度小于原字符串的长度则返回原字符串

 

 

18、lower

 lower(self)返回将字符串中所有大写字符转换为小写后生成的字符串
 >>> name = 'LIUYAO'
 >>> print (name.lower())
 liuyao

19、lstrip

 lstrip(self, chars=None)返回截掉字符串左边的空格或指定字符后生成的新字符串
 >>> name = 'liuyaoliuyaoliuyao'
 >>> print (name.lstrip('liu'))
 yaoliuyaoliuyao

20、partition 返回一个3元的元组，第一个为分隔符左边的子串，第二个为分隔符本身，第三个为分隔符右边的子串。

 #!/usr/bin/python

 str = "http://www.w3cschool.cc/"

 print str.partition("://")

 ('http', '://', 'www.w3cschool.cc/')

21、replace 返回字符串中的 旧字符串替换成新字符串后生成的新字符串，如果指定第三个参数2次，则替换不超过2 次

 name= 'ni shi wo shi shei shi bi shi'
 print(name.replace('shi','ta'))
 print(name.replace('shi','ta',2))
4 ni ta wo ta shei ta bi ta
5 ni ta wo ta shei shi bi shi

22、split

 name= 'ni shi,wo shi,shei shi,bi shi'
 print(name.split())#默认是以空格为分隔符
 print (name.split(',',2)) #可以定义分隔符和分割次数

 ['ni', 'shi,wo', 'shi,shei', 'shi,bi', 'shi']
 ['ni shi', 'wo shi', 'shei shi,bi shi']

23、splitlines  Python splitlines() 按照行分隔，返回一个包含各行作为元素的列表，如果 num 指定则仅切片 num 个行.

 name= 'ni shi\nwo shi\nshei shi\nbi shi\n'
 print(name)
 print(name.splitlines())
 print (name.splitlines(1))

 ni shi
 wo shi
 shei shi
 bi shi
 ['ni shi', 'wo shi', 'shei shi', 'bi shi']
 ['ni shi\n', 'wo shi\n', 'shei shi\n', 'bi shi']

24、startswith 用于检查字符串是否是以指定子字符串开头，如果是则返回 True，否则返回 False。

 name= 'ni shi wo shi shei shi bi shi'
 print(name)
 print(name.startswith('ni'))
 print(name.startswith('wo'))

 ni shi wo shi shei shi bi shi
 True
 False

25、swapcase 用于对字符串的大小写字母进行转换

 name= 'Ni Shi wo shi shei shi bi shi'
 print(name)
 print(name.swapcase())

 Ni Shi wo shi shei shi bi shi
 nI sHI WO SHI SHEI SHI BI SHI

26、upper 将小写字母转换为大写

 name= 'Ni Shi wo shi shei shi bi shi'
 print(name)
 print(name.upper())

 Ni Shi wo shi shei shi bi shi
 NI SHI WO SHI SHEI SHI BI SHI

27、zfill 返回指定长度的字符串，指定字符串的长度大于字符长度。原字符串右对齐，前面填充0。

 name= 'Ni Shi'
 print(name.zfill(5))
 print(name.zfill(10))

 Ni Shi
 0000Ni Shi

三、字典

1、查看

 id_db={
     12345:{
         "name":"zkk",
         "age":20,
         "job":"it",
     },
     23456:{
         "name":"zxc",
         "age":20,
         "job":"it",
     }
 }
 print(id_db[12345])

 {'name': 'zkk', 'age': 20, 'job': 'it'}

2、修改

 id_db={
     12345:{
         "name":"zkk",
         "age":20,
         "job":"it",
     },
     23456:{
         "name":"zxc",
         "age":20,
         "job":"it",
     }
 }
 id_db[12345]["name"] = "zkk2"  #修改
 print(id_db[12345])

 {'age': 20, 'job': 'it', 'name': 'zkk2'}

3、添加v

 id_db={
     12345:{
         "name":"zkk",
         "age":20,
         "job":"it",
     },
     23456:{
         "name":"zxc",
         "age":20,
         "job":"it",
     }
 }
 id_db[12345]["qq"] = 123321 #添加一个v
 print(id_db[12345])

 {'name': 'zkk', 'job': 'it', 'age': 20, 'qq': 1207088427}}

4、获取items，keys，values

 id_db={
     12345:{
         "name":"zkk",
         "age":20,
         "job":"it",
     },
     23456:{
         "name":"zxc",
         "age":20,
         "job":"it",
     }
 }
 print((id_db.values()))
 print((id_db.items()))
 print((id_db.keys()))

 dict_values([{'name': 'zxc', 'age': 20, 'job': 'it'}, {'name': 'zkk', 'age': 20, 'job': 'it'}])
 dict_items([(23456, {'name': 'zxc', 'age': 20, 'job': 'it'}), (12345, {'name': 'zkk', 'age': 20, 'job': 'it'})])
 dict_keys([23456, 12345])

5、判断key在不在字典

 id_db={
     12345:{
         "name":"zkk",
         "age":20,
         "job":"it",
     },
     23456:{
         "name":"zxc",
         "age":20,
         "job":"it",
     }
 }
 print(12345 in id_db)

 True

6、keys不存在的时候，默认返回None，可以定义返回值

 id_db={
     12345:{
         "name":"zkk",
         "age":20,
         "job":"it",
     },
     23456:{
         "name":"zxc",
         "age":20,
         "job":"it",
     }
 }
 print(id_db.setdefault(123456))

 None

7、fromkeys()   函数用于创建一个新字典，以序列seq中元素做字典的键，value为字典所有键对应的初始值。

 dic2 = {
     'name':'liyuemei',
     34567:{
         'name':'zrz',
     }
 }
 set = ['aa','bb','cc']
 print(dic2.fromkeys(set,10))#名字只是引用，和字典dic2没有关系
 print(dic2)

 {'bb': 10, 'aa': 10, 'cc': 10}
 {'name': 'liyuemei', 34567: {'name': 'zrz'}}

8、clear清空；pop指定删除；popitem随机删除