2-07 문자열 유형 설명

데이터 유형 - 문자열
문자열은 질서정연한 문자 집합으로 기본적인 텍스트 정보를 저장하고 나타내는 데 사용되며, 한 쌍의 단일, 더블 또는 세 인용부호 사이에 포함된 내용을 문자열이라고 부른다.
생성:
 

s = 'Hello,beauty!How are you?'

 
특징:

순서

변경 불가

자주 사용: isdigit replace find count index split strip center format join

s = 'Hello World!'

#     ，     
print(s.swapcase())

#     
print(s.capitalize())

#      
print(s.casefold())

#             ：*******************Hello World!*******************
print(s.center(50,'*'))

#       
print(s.count('o'))    #2
print(s.count('o',0,5)) #        1

#              
print(s.endswith('!'))  # True

#  tab ， tab        
s1 = 'a\tb'
print(s1)     #  a    b
print(s1.expandtabs(20)) #   a                   b

#      ，    
print(s.find('W'))   #6
print(s.find('W',0,3))  #              -1

#      
s3 = 'my name is {0},i am {1} years old.'
print(s3.format('Alex',22))                     # my name is Alex,i am 22 years old.

s3 = 'My name is {name}, I am {age} years old.'
print(s3.format(name='Alex',age = '22'))

 

>>> #         
...
>>> s = 'Hello World!'
>>> s.index('o')
4
>>> s.index('o',5,6)
Traceback (most recent call last):
  File "", line 1, in 
ValueError: substring not found

>>> #        
...
>>> '22b'.isalnum()
True
>>> '22b*'.isalnum()
False

>>> #     
...
>>> '222'.isalpha()
False
>>> 'abcc'.isalpha()
True
>>> '22bb'.isalpha()
False

>>> #     
...
>>> '234'.isdecimal()
True
>>> '2ab4'.isdecimal()
False
>>> '22.22'.isdecimal()
False
>>>

>>> #         
...
>>> '332'.isidentifier()
False
>>> 'd332'.isidentifier()
True
>>>

>>> #       
...
>>> 'ab'.islower()
True
>>> 'ab3'.islower()
True
>>> 'abAA'.islower()
False

>>> #             
...
>>> 'ab4'.isnumeric()
False
>>> '114'.isnumeric()
True
>>>

>>> #       
...
>>> '2bg'.isprintable()
True

>>> #       
...
>>> ' '.isspace()
True
>>> 'ab'.isspace()
False
>>> 'a b'.isspace()
False

>>> #     
...
>>> 'ABC'.isupper()
True
>>>
>>> 'abA'.isupper()
False

 

>>> #                                                                                                                                                                                                 
...
>>> names = ['alex','jack','rain']                                                                                                                                                             
>>> ''.join(names)                                                                                                                                                                                    
'alexjackrain'
>>> ' '.join(names)
'alex jack rain'
>>> '*'.join(names)
'alex*jack*rain'
>>>

>>> #        ，                                                                                                                                                                                        
...
>>> s = 'Hello World!'                                                                                                                                                                                
>>> s.ljust(50)
'Hello World!                                      '
>>> s.ljust(50,'-')
'Hello World!--------------------------------------'

>>> #                                                                                                                                                                                                 
...
>>> s = 'Hello World!'                                                                                                                                                                          
>>> s.lower()
'hello world!'
>>> #                                                                                                                                                                                                 
...
>>> s.upper()
'HELLO WORLD!'

>>> #       、  、tab                                                                                                                                                                                   
...
>>> s = '
 hello world  '                                                                                                                                                                            
>>> s.lstrip()
'hello world  '
>>> s.rstrip()
'
 hello world'

>>> #                     
>>> str_in = 'abcdef'                                                                                                                                                                        
>>> str_out = '!@#$%^'
>>> table=str.maketrans(str_in,str_out)
>>> 'abc'.translate(table)
'!@#'

>>> #     
>>> s.replace('o','-')
'Hell- W-rld'
>>> s.replace('o','-',1)
'Hell- World'

>>> #                                                                                                                                                                                                 
...
>>> s = 'hello world!'                                                                                                                                                                                
>>> s.rfind('o')
7
>>> s.rindex('o')
7

>>> #                                                                                                                                                                                                 
...
>>> s = 'hello world' 
>>> s.split()
['hello', 'world']
>>> s.split('o')
['hell', ' w', 'rld']
>>> s.split('o',1)
['hell', ' world']
>>> s.rsplit('o',1)
['hello w', 'rld']

>>> #                                                                                                                                                                                                
...
>>> s = 'a
b
c
dld
'
>>> s.splitlines()
['a', 'b', 'c', 'dld']

>>> #                                                                                                                                                                                                 
...
>>> s = 'hello world'
>>> s.startswith('he')
True
>>> s.startswith('hello')
True
>>> s.startswith('heh')
False

>>> s.endswith('d')
True

>>> #          ，    0                                                                                                                                                                                 
...
>>> s = 'hello world'
>>> s.zfill(40)
'00000000000000000000000000000hello world'

 
전재 대상:https://www.cnblogs.com/echo-kid-coding/p/11163281.html