Question

目前，我有一些类似的代码

try:
    somecode
except Exception as Error:
    fallbackcode

现在，我想向后备代码添加另一个后备代码在python中进行嵌套try / catch的最佳实践是什么？

try:
    somecode
except Exception as Error:
    try:
        fallbackcode
    except Exception as Error:
        nextfallbackcode

产生意图错误

Answer 1

您应该能够完全按照问题的实现方式来进行嵌套的try / except块。

这是另一个例子：

import os

def touch_file(file_to_touch):
    """
    This method accepts a file path as a parameter and
    returns true/false if it successfully 'touched' the file
    :param '/path/to/file/'
    :return: True/False
    """    
    file_touched = True

    try:
        os.utime(file_to_touch, None)
    except EnvironmentError:
        try:
            open(file_to_touch, 'a').close()
        except EnvironmentError:
            file_touched = False

    return file_touched

Answer 2

如果所有回调和后备具有相同的API接口，则可以使用循环来重写逻辑

for code in [somecode, fallbackcode, nextfallbackcode]:
    try:
        code(*args, **kwargs)
        break
    except Exception as Error:
        continue
else:
    raise HardException

这是首选方法，而不是多层嵌套异常块。

Answer 3

您可以这样更改它：

try:
    try:
        somecode
    except Exception as Error:
        fallbackcode
except Exception as Error:
    nextfallbackcode

Answer 4

您可以使用函数来处理错误：

def func0():
    try:
        somecode
    except:
        other_func()

def func1():
    try:
        somecode
    except:
        func0()

Python：嵌套的try catch处理

4 个答案: