Question

我有一个日志文件。我只想以“ yyyy-mm-dd”格式打印以日期开头的日志文件行，而忽略所有其他行。日志文件如下所示： ” 流程开始

2018-01-02 This is good
2017-03-22 This is also good
What were you doing on 20-09-2016
2016-09-20 I was working
log file ends

输出应为：

2018-01-02 This is good
2017-03-22 This is also good
2016-09-20 I was working

Answer 1

此正则表达式here的说明。

import re

data = """
2018-01-02 This is good
2017-03-22 This is also good
What were you doing on 20-09-2016
2016-09-20 I was working
log file ends
"""

for line in re.findall(r'^\d{4}-\d{2}-\d{2}.*$', data, flags=re.M):
    print(line)

此打印：

2018-01-02 This is good
2017-03-22 This is also good
2016-09-20 I was working

Answer 2

您可以使用正则表达式：

^\d{4}-\d{2}-\d{2}.*$

Python代码段：

import re
str = """
2018-01-02 This is good
2017-03-22 This is also good
What were you doing on 20-09-2016
2016-09-20 I was working
log file ends
"""

print(re.findall(r"^\d{4}-\d{2}-\d{2}.*$",str,re.MULTILINE));

输出

['2018-01-02 This is good', '2017-03-22 This is also good', '2016-09-20 I was working']

Answer 3

使用re.match

例如：

import re
s = """2018-01-02 This is good
2017-03-22 This is also good
What were you doing on 20-09-2016
2016-09-20 I was working
log file ends"""

for line in s.splitlines():
    if re.match(r"\d{4}-\d{2}-\d{2} ", line):    #Check if each line matches condition.
        print(line)

输出：

2018-01-02 This is good
2017-03-22 This is also good
2016-09-20 I was working

Answer 4

使用正则表达式fullmatch每行：

for line in lines:
    m = re.fullmatch('^(\d{4}-\d{2}-\d{2}) (.*)$', line)
    if m:
        print(m.group())

输出：

2018-01-02 This is good
2017-03-22 This is also good
2016-09-20 I was working

在Python中打印以日期格式“ yyyy-mm-dd”开头的日志文件的行

4 个答案: