Python标准库--string模块

Posted 2020-09-21

string中包含了处理文本的常量和模板

常量

print(string.whitespace)
print(string.ascii_lowercase)
print(string.ascii_uppercase)
print(string.ascii_letters)
print(string.digits)
print(string.hexdigits)
print(string.octdigits)
print(string.punctuation)
print(string.printable)

"""
     

abcdefghijklmnopqrstuvwxyz
ABCDEFGHIJKLMNOPQRSTUVWXYZ
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
0123456789
0123456789abcdefABCDEF
01234567
!"#$%&‘()*+,-./:;<=>[email protected][\]^_`{|}~
0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&‘()*+,-./:;<=>[email protected][\]^_`{|}~     


"""
# 第一个是几个空行,Windows输出有点问题

函数

capwords():每个单词首字母大写,可自定义单词间分隔符

s = ‘This is a dog‘
print(s)
print(string.capwords(s))

s2 = ‘This-is-a-dog‘
print(s2)
print(string.capwords(s2, ‘-‘))

"""
This is a dog
This Is A Dog
This-is-a-dog
This-Is-A-Dog

"""

模板

substitute() 传入模板变量, 没有就报错

safe_substitute() 捕获异常,原样输出

values = {‘var‘: ‘boo‘}

t = string.Template("""
    Variable        ：$var
    Excape          : $$
    Variable in text: ${var}iable
""")

print(t.substitute(values))

t2 = string.Template("$var is here but $missing is not provided")

try:
    print(t2.substitute(values))
except KeyError as err:
    print(‘ERROR:‘, str(err))

print(t2.safe_substitute(values))

"""

    Variable        ：boo
    Excape          : $
    Variable in text: booiable

ERROR: ‘missing‘
boo is here but $missing is not provided
"""

$$ 输出 $

自定义模板类继承string中的模板类,可自定义变量定界符,和变量查找规则

class MyTemplate(string.Template):
    delimiter = ‘%‘
    idpattern = ‘[a-z]+_[a-z]+‘

Formatter