匹配列表中不带.csv扩展名的字符串的正则表达式

如果您真的想使用正则表达式,可以使用 re.sub 若要删除扩展名,如果不存在,则只保留字符串:

[re.sub(r'\.csv$', '', i) for i in data_files]

['ap_2010',
 'class_size',
 'demographics',
 'graduation',
 'hs_directory',
 'sat_results']

os 处理与文件名有关的任何内容的模块:

[os.path.splitext(i)[0] for i in data_files]

['ap_2010',
 'class_size',
 'demographics',
 'graduation',
 'hs_directory',
 'sat_results']

如果您想要regex,解决方案是 r'(.*)\.csv

for i in data_files:
    regex = re.findall(r'(.*)\.csv', i)
    print(regex)

把绳子分开 '.' [-1] ). 如果这是 'csv' 然后是一个csv文件。

for i in data_files:
    if i.split('.')[-1].lower() == 'csv':
        # It is a CSV file
    else:
        # Not a CSV

# Input
data_files = [ 'ap_2010.csv', 'class_size.csv', 'demographics.csv', 'graduation.csv', 'hs_directory.csv', 'sat_results.csv' ]

import re

pattern = '(?P<filename>[a-z0-9A-Z_]+)\.csv'
prog = re.compile(pattern)

# `map` function yields:
#  - a `List` in Python 2.x
#  - a `Generator` in Python 3.x
result = map(lambda data_file: re.search(prog, data_file).group('filename'), data_files)

l = [
"ap_2010.csv",
"class_size.csv",
"demographics.csv",
"graduation.csv",
"hs_directory.csv",
"sat_results.csv"]

print([i.rstrip('.'+i.split('.')[-1]) for i in l])