Python捕获异常堆栈信息的几种方法(小结)

脚本专栏 2024/11/8 佚名

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程序出错的时候，我们往往需要根据异常信息来找到具体出错的代码。简单地用print打印异常信息并不能很好地追溯出错的代码：

# -*- coding: utf-8 -*-
 
 
def foo(a, b):
  c = a + b
  raise ValueError('test')
  return c
 
 
def bar(a):
  print('a + 100:', foo(a, 100))
 
 
def main():
  try:
    bar(100)
  except Exception as e:
    print(repr(e))
 
if __name__ == '__main__':
  main()

输出：

ValueError('test',)

打印的异常信息不够详细，对错误追踪没有多大帮助。这时候异常堆栈信息就派上用场了。下面简单介绍几种打印异常堆栈信息的方法。

1.最简单的方法之一就是使用logging.exception

# -*- coding: utf-8 -*-
import logging
 
 
def foo(a, b):
  c = a + b
  raise ValueError('test')
  return c
 
 
def bar(a):
  print('a + 100:', foo(a, 100))
 
 
def main():
  try:
    bar(100)
  except Exception as e:
    logging.exception(e)
 
if __name__ == '__main__':
  main()

输出：

ERROR:root:test
Traceback (most recent call last):
File "E:/git_work/scrapy_ppt/test.py", line 16, in main
bar(100)
File "E:/git_work/scrapy_ppt/test.py", line 11, in bar
print('a + 100:', foo(a, 100))
File "E:/git_work/scrapy_ppt/test.py", line 6, in foo
raise ValueError('test')
ValueError: test

从异常堆栈信息中我们可以不费力气就找出错误代码是哪一行。

2.其它方法：

# -*- coding: utf-8 -*-
import traceback
import sys
 
 
def foo(a, b):
  c = a + b
  raise ValueError('test')
  return c
 
 
def bar(a):
  print('a + 100:', foo(a, 100))
 
 
def main():
  try:
    bar(100)
  except Exception as e:
    # 方法二
    traceback.print_exc()
 
    # 方法三
    msg = traceback.format_exc()
    print(msg)
 
    et, ev, tb = sys.exc_info()
    # 方法四
    traceback.print_tb(tb)
 
    # 方法五
    traceback.print_exception(et, ev, tb)
 
    # 方法六
    msg = traceback.format_exception(et, ev, tb)
    for m in msg:
      print(m)
 
if __name__ == '__main__':
  main()

Python捕获异常堆栈信息,Python异常堆栈信息