Python 错误处理 : finally vs. 新行 dedented

当使用 try 和 except 进行错误处理时，是显式调用 finally 还是直接转到与异常代码分离的新行，这是否重要？例如，有没有什么情况下下面的两个函数会产生不同的结果？

#Function 1 with finally
def final(x):
    try:
        print(x*x)

    except:
        print("Error")

    finally:
        print("End Function")


#Function 2 with new line dedent
def dedent(x):
    try:
        print(x*x)

    except:
        print("Error")

    print("End Function")

更新:
感谢您对 finally 运行的解释，即使 except 块中有错误。我想指出的另一件事是，即使您在 except 块中返回一个对象， finally 块也会运行。例如，即使在 return 之后，下面的函数 3 也会打印，而函数 4 则不会。

#Function 3 with finally
def final(x):
    try:
        print(x*x)

    except:
        return 3

    finally:
        print("End Function 3")


#Function 4 with new line dedent
def dedent(x):
    try:
        print(x*x)

    except:
        return 3

    print("End Function 4")

test1 = final('test')
test2 = dedent('test')

最佳答案

已经提到的 except 块中存在错误:

def final(x):
    try:
        print(x*x)

    except:
        print("Error")
        damnit

    finally:
        print("End Function")

def dedent(x):
    try:
        print(x*x)

    except:
        print("Error")
        damnit

    print("End Function")

try:
    final("a")
except Exception as e:
    print("There was an error:", e)
#>>> Error
#>>> End Function
#>>> There was an error: global name 'damnit' is not defined

try:
    dedent("a")
except Exception as e:
    print("There was an error:", e)
#>>> Error
#>>> There was an error: global name 'damnit' is not defined

还有 return 行为:

def final(x):
    try:
        print(x*x)

    except:
        print("Error")
        return "Return inside"

    finally:
        print("End Function")
        return "Return outside"

def dedent(x):
    try:
        print(x*x)

    except:
        print("Error")
        return "Return inside"

    print("End Function")
    return "Return outside"

try:
    final("a")
except Exception as e:
    print("There was an error:", e)
#>>> Error
#>>> End Function
#>>> 'Return outside'

try:
    dedent("a")
except Exception as e:
    print("There was an error:", e)
#>>> Error
#>>> 'Return inside'

关于Python 错误处理 : finally vs. 新行 dedented，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/19038925/