Python: 练习 正则表达式 匹配文件名/扩展名

# 匹配文件名
import re

file_name0 = "123.test.abc.zip"
file_name1 = ".test.abc.zip"
file_name2 = ".zip"
file_name3 = "test"
re_ = r".*?(?=\.[^\.]*$)|[^\.]+"
file_name_0 = re.match(re_, file_name0)
file_name_1 = re.match(re_, file_name1)
file_name_2 = re.match(re_, file_name2)
file_name_3 = re.match(re_, file_name3)
print(file_name_0)
print(file_name_1)
print(file_name_2)
print(file_name_3)

# 匹配扩展名
import re

file_name0 = "123.test.abc.zip"
file_name1 = ".test.abc.zip"
file_name2 = ".zip"
file_name3 = "test"
# re_ = r".*?(?=\.[^\.]*$)|[^\.]+"
re_ = r"\.[^\.]*$"
file_name_0 = re.search(re_, file_name0)
file_name_1 = re.search(re_, file_name1)
file_name_2 = re.search(re_, file_name2)
file_name_3 = re.search(re_, file_name3)
if not file_name_3:
    file_name_3=""
print(file_name_0)
print(file_name_1)
print(file_name_2)
print(file_name_3)