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  • python之字符串函数

    1.  endswith()  startswith()

    1 # 以什么什么结尾
    2 # 以什么什么开始
    3 test = "alex"
    4 v = test.endswith('ex')
    5 v = test.startswith('ex')
    6 print(v)
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    2. expandtabs()

    1 test = "1	2345678	9"
    2 v = test.expandtabs(6)
    3 print(v,len(v))
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    3. find()

    1 # 从开始往后找,找到第一个之后,获取其未知
    2 # > 或 >=
    3 test = "alexalex"
    4 # 未找到 -1
    5 v = test.find('e')
    6 print(v)
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    4.  index()

    1 # index找不到,报错   忽略
    2 test = "alexalex"
    3 v = test.index('a')
    4 print(v)
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    5. format()  format_map()

     1 # 格式化,将一个字符串中的占位符替换为指定的值
     2 test = 'i am {name}, age {a}'
     3 print(test)
     4 v = test.format(name='alex',a=19)
     5 print(v)
     6 
     7 test = 'i am {0}, age {1}'
     8 print(test)
     9 v = test.format('alex',19)
    10 print(v)
    11 
    12 # 格式化,传入的值 {"name": 'alex', "a": 19}
    13 test = 'i am {name}, age {a}'
    14 v1 = test.format(name='df',a=10)
    15 print(v1)
    16 v2 = test.format_map({"name": 'alex', "a": 19})
    17 print(v2)
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    6. isalnum()

    1 # 字符串中是否只包含 字母和数字
    2 test = "er;"
    3 v = test.isalnum()
    4 print(v)
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     7.capitalize() 首字母大写

    1 test = "sqy"
    2 v = test.capitalize()
    3 print(v)
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    8. casefold()  lower() 所有变小写,casefold更牛逼,很多未知的对相应变小写

    1 test = "sqy"
    2 v1 = test.casefold()
    3 print(v1)
    4 v2 = test.lower()
    5 print(v2)
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    9. center() 置宽度,并将内容居中

    1 # 20 代指总长度
    2 # *  空白未知填充,一个字符,可有可无
    3 test = "sqy"
    4 v = test.center(20,"中")
    5 print(v)
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    10.  ljust() rjust() zfill()

     1 # test = "alex"
     2 # v = test.ljust(20,"*")
     3 # print(v)
     4 
     5 # test = "alex"
     6 # v = test.rjust(20,"*")
     7 # print(v)
     8 
     9 # test = "alex"
    10 # v = test.zfill(20)
    11 # print(v)
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    11. count() 去字符串中寻找,寻找子序列的出现次数

    1 test = "aLexalexr"
    2 v = test.count('ex')
    3 print(v)
    4 
    5 test = "aLexalexr"
    6 v = test.count('ex',5,6)
    7 print(v)
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    12. isalpha() 是否是字母,汉子

    1 test = "as大多数df"
    2 v = test.isalpha()
    3 print(v)
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    13. isdecimal()  isdigit() isnumeric()  当前输入是否是数字

    1 test = "②" # 1,②,儿
    2 v1 = test.isdecimal()
    3 v2 = test.isdigit()
    4 v3 = test.isnumeric()
    5 print(v1,v2,v3)
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    14.isprintable() 是否存在不可显示的字符

    1 # 	   制表符
    2 # 
       换行
    3 test = "gdds	fdsfd"
    4 v = test.isprintable()
    5 print(v)
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    15. isspace()  判断是否全部是空格

    1 test = "  ass"
    2 v = test.isspace()
    3 print(v)
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    16.  istitle() title() 判断是否是标题

    1 test = "Return True if all cased characters in S are uppercase and there is"
    2 v1 = test.istitle()
    3 print(v1)
    4 v2 = test.title()
    5 print(v2)
    6 v3 = v2.istitle()
    7 print(v3)
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    17. join() 将字符串中的每一个元素按照指定分隔符进行拼接

    1 test = "你是风儿我是沙"
    2 print(test)
    3 t = ' '
    4 v = "_".join(test)
    5 print(v)
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    18.  islower() lower()  isupper() upper()

    1 test = "Alex"
    2 v1 = test.islower()
    3 v2 = test.lower()
    4 print(v1, v2)
    5 
    6 v1 = test.isupper()
    7 v2 = test.upper()
    8 print(v1,v2)
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    19. lstrip()  rstrip() strip( 移除指定字符串 有限最多匹配

     1 test = "
    xas12xa
    	xax1221axa  "
     2 v = test.lstrip('xa')
     3 v = test.rstrip('9lexxexa')
     4 v = test.strip('xa')
     5 print(v)
     6 
     7 test.lstrip()
     8 test.rstrip()
     9 test.strip()
    10 # 去除左右空白
    11 v = test.lstrip()
    12 v = test.rstrip()
    13 v = test.strip()
    14 print(v)
    15 print(test)
    16 # 去除	 
    
    17 v = test.lstrip()
    18 v = test.rstrip()
    19 v = test.strip()
    20 print(v)
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    20. maketrans()  translate()  对应关系替换

    1 v = "asidufkasd;fiuadkf;adfkjalsdjf"
    2 m = str.maketrans("aeiou", "12345")
    3 new_v = v.translate(m)
    4 print(new_v)
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    21. partition()  rpartition() 分割为三部分

    1 test = "testasdsddfg"
    2 v = test.partition('s')
    3 print(v)
    4 v = test.rpartition('s')
    5 print(v)
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    22. split() rsplit()  splitlines()

     1 test = "sqys"
     2 v = test.split('s',2)
     3 print(v)
     4 v = test.rsplit()
     5 print(v)
     6 
     7 
     8 # 23 分割,只能根据,truefalse:是否保留换行
     9 # test = "asdfadfasdf
    asdfasdf
    adfasdf"
    10 # v = test.splitlines(False)
    11 # print(v)
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    23. swapcase() 大小写转换

    1 test = "aLex"
    2 v = test.swapcase()
    3 print(v)
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    24. isidentifier() 字母,数字,下划线 : 标识符 def class

    1 a = "de12_f"
    2 v = a.isidentifier()
    3 print(v)
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    25.replace()  将指定字符串替换为指定字符串

    1 test = "alexalexalex"
    2 v = test.replace("ex",'bbb')
    3 print(v)
    4 v = test.replace("ex",'bbb',2)
    5 print(v)
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     26.灰魔法

      一、for循环   

     1 test = "返回到合肥东方红刚才修改"
     2 # for 变量名 in 字符串:
     3 #     变量名
     4 # break
     5 # continue
     6 
     7 
     8 index = 0
     9 while index < len(test):
    10     v = test[index]
    11     print(v)
    12 
    13     index += 1
    14 print('=======')
    15 
    16 for zjw in test:
    17     print(zjw)
    18 
    19 test = "好方法个地方个地方刚发的"
    20 for item in test:
    21     print(item)
    22     break
    23 
    24 for item in test:
    25     continue
    26     print(item)
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      二、索引,下标,获取字符串中的某一个字符

    1 test = "好方法个地方个地方刚发的"
    2 v = test[3]
    3 print(v)
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      三、切片

    1 test = "好方法个地方个地方刚发的"
    2 v = test[0:10] # 0=<  <1
    3 print(v)
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      四、获取长度

    1 # Python3: len获取当前字符串中由几个字符组成
    2 test = "好方法个地方个地方刚发的"
    3 v = len(test)
    4 print(v)
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    27. range()  获取连续或不连续的数字

     1 # Python2中直接创建在内容中
     2 # python3中只有for循环时,才一个一个创建
     3 v = range(10)
     4 v = range(3,10)
     5 v = range(1,10,2)
     6 # 帮助创建连续的数字,通过设置步长来指定不连续
     7 v = range(0, 100, 5)
     8 
     9 for item in v:
    10     print(item)
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     28.zip()

     1 # print(list(zip(('a','n','c'),(1,2,3))))
     2 # print(list(zip(('a','n','c'),(1,2,3,4))))
     3 # print(list(zip(('a','n','c','d'),(1,2,3))))
     4 #
     5 # p={'name':'alex','age':18,'gender':'none'}
     6 # print(list(zip(p.keys(),p.values())))
     7 # print(list(p.keys()))
     8 # print(list(p.values()))
     9 #
    10 print(list(zip(['a','b','c'],'12345')))
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  • 原文地址:https://www.cnblogs.com/sqy-yyr/p/9329178.html
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