Python学习总结----基础篇4

字符串操作

name= 'ykyk'
>>> name.capitalize ()
'Ykyk'

name='YKYK'
>>> name.casefold()
'ykyk'

name='ykyk'
>>> name.center(50,"-")
'-----------------------ykyk-----------------------'

>>> name.count('y')
2

>>> name.encode()
b'ykyk'            将字符串编码成bytes格式

>>> name.endswith('k')
True
>>> name.endswith('y')
False 判断字符串是否以k结尾

>>> name.find('y')
0
>>> name.find('l')
-1
>>> name.find('k')
1

查找字符，找到返回索引值，找不到返回-1

format：

>>> info='My name is {}, and age is {}'
>>> info.format('ykyk',22)
'My name is ykyk, and age is 22'
>>> info='My name is {1}, and age is {0}'
>>> info.format('ykyk',22)
'My name is 22, and age is ykyk'
>>> info='My name is {name}, and age is {age}'
>>> info.format(age=22,name='ykyk')
'My name is ykyk, and age is 22'

>>> info.format_map({'name':"ykyk",'age':'22'})
'My name is ykyk, and age is 22'

>>>info.index('a')
4

>>>'sd2'.isalnum()
True

>>>'9'.isdigit()
True

>>>name.isnumeric()
False

>>> '10'.isnumeric()
True

>>> name.isprintable()
True

>>>name.isspace()
False
>>> ' '.isspace()
True

>>> '|'.join(['ykyk','tian'])
'ykyk|tian'

maketrans

>>> intab='aeiou'
>>> outab='12345'

>>> trantab = str.maketrans(intab,outab)

str='this is a string example'
>>> str.translate(trantab)
'th3s 3s 1 str3ng 2x1mpl2'

>>> info.partition('is')
('My name ', 'is', ' {name}, and age is {age}')

>>> info.swapcase()
'mY NAME IS {NAME}, AND AGE IS {AGE}'

>>> info.zfill(60)
'0000000000000000000000000My name is {name}, and age is {age}'

>>> info.ljust(60,'-')
'My name is {name}, and age is {age}-------------------------'

>>> info.rjust(60,'#')
'#########################My name is {name}, and age is {age}'

>>> a='dsfasdfas_你好1234'
>>> a.isidentifier()
True

检测一段字符串是否可以被当作标志符，即是否符合变量命名规则