python第三课,字符串的魔法（续） 

  1 # expandtabs,断句17
  2 # s = "username\temail\tpassword\nluofei\tluofei@qq.com\terwer\nluofei\tluofei@qq.com\tyrth\n"
  3 # m = s.expandtabs(17)
  4 # print(m)
  5 
  6 
  7 # isalpha判断是否字母
  8 # test = "ssdsg"
  9 # v = test.isalpha()
 10 # print(v)
 11 
 12 
 13 # # # 判断是否数字 只判断首字母？
 14 # test = "6767rr6"
 15 # v = test.isalnum()
 16 # print(v)
 17 
 18 
 19 # # 字母，数字，下划线：标识符  判断字符串是否是有效的 Python 标识符,可用来判断变量名是否合法
 20 # test = "6767rr6"
 21 # v = test.isidentifier()
 22 # print(v)
 23 
 24 # isnumeric可以判断中文的数字
 25 # test = "三"
 26 # v = test.isnumeric()
 27 # v2 = test.isdigit()
 28 # print(v,v2)
 29 
 30 # 是否存在不可显示的字符：isprintable   \t是制表符，\n是换行
 31 # test = "sdofad\tfofasdn"
 32 # v = test.isprintable()
 33 # print(v)
 34 
 35 # 判断是否全部是空格
 36 # test = " "
 37 # v = test.isspace()
 38 # print(v)
 39 
 40 # itle 转化首字母大写，isitle，判断是否为都首字母大写的标题
 41 # test = "Rnsdl sdoan adfoam adldfd is"
 42 # v = test.title()
 43 # print(v)
 44 
 45 # ******************************
 46 # join，将字符串中的每一个元素，按照指定分隔符拼接。内部逻辑是循环加入
 47 # test = "你是风儿我是沙"
 48 # t = " "
 49 # v = t.join(test)
 50 # print(v,t)
 51 # s = "插一脚".join(test)
 52 # print(s)
 53 
 54 # ljust,rjust填充字符
 55 # test = "alex"
 56 # v = test.ljust(20,"*")
 57 # s = test.rjust(30,"_")
 58 # print(v,s)
 59 #
 60 
 61 # 判断小写和变成小写  扩展：判断和变成大写
 62 # test = "Ales"
 63 # v1 = test.islower()
 64 # v2 = test.lower()
 65 # v3 = test.isupper()
 66 # v4 = test.upper()
 67 # print(v1,v2,v3,v4)
 68 
 69 
 70 # 去除左右空白 \t \n,还可以在参数中指定字符去掉
 71 # test = " alex "
 72 # v1 = test.lstrip()
 73 # v2 = test.rstrip()
 74 # v3 = test.strip()
 75 # print(v1,v2,v3)
 76 # 参数示例 test.strip("ex") 找参数中的匹配项
 77 
 78 # 按照对应关系转化
 79 # test = "你dfhah39y23ehh"
 80 # m = str.maketrans("12345","aeiou")
 81 # testtrans = test.maketrans(m)
 82 # print(testtrans)
 83 
 84 # 字符串分割
 85 # test = "agetetegwefe"
 86 # v = test.partition("e")
 87 # v1 = test.rpartition("t")
 88 # v2 = test.split("w")
 89 # v3 = test.rsplit("f",2)
 90 # print(v,v1,v2,v3)
 91 
 92 # 只能根据换行分割  参数 True False 是否显示\n
 93 # test = "agetete\ndfaefwe\ndfsfsgwefe"
 94 # v = test.splitlines(False)
 95 # print(v)
 96 
 97 
 98 # 大小写相互转化
 99 # test = "sofejfoEFI"
100 # v = test.swapcase()
101 # print(v)

 

posted @ 2022-02-21 23:58  黎明前登顶  阅读(36)  评论(0)    收藏  举报