Question

如何捕获内部错误＆＃34;否则＆＃34;那＆＃34;其他＆＃34;在里面＆＃34;尝试＆＃34;。这是代码：

try:
    if appcodex == app:
        print "AppCode Confirmed"
        if acccodex == acc:
            print "Access Code Confirmed"
            if cmdcodex == cmd:
                print "Command Code Confirmed"
                print "All Code Confirmed, Accessing URL..."
            else:
                print "Command Code not found"
        else:
            print "Access Code not found"
    else:
        print "AppCode not found"
except:
    print "Error : Code doesn't match..."

当cmdcodex / cmd没有输入时，如何引发"CommandCode not found"而不是"Error : Code doesn't match..."。

Answer 1

您需要创建自己的例外并提升它。它就像创建一个继承自Exception的类一样简单，然后使用raise：

>>> class CommandCode(Exception):
...     pass
...
>>> raise CommandCode('Not found')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
__main__.CommandCode: Not found

Answer 2

通常你会得到“错误：代码不匹配......”而不是“找不到命令代码”。为什么？答案是基本的：你需要理解handling exceptions in Python的基本概念。

在你的特殊情况下，你必须在试试中包装那段代码..除了块之外，像这样：

try:
  if appcodex == app:
    print "AppCode Confirmed"
    if acccodex == acc:
        print "Access Code Confirmed"
        try:
           if cmdcodex == cmd:
            print "Command Code Confirmed"
            print "All Code Confirmed, Accessing URL..."
        except:
            print "Command Code not found"
    else:
        print "Access Code not found"
  else:
    print "AppCode not found"
except:
    print "Error : Code doesn't match..."

总结一下情况：您可以根据需要嵌套必要的try ... except块。但是你应该遵循这个PEP

在其他内部捕获错误并尝试

2 个答案: