擅长:python、mysql、java
<p>它有助于确定回溯问题所指的“什么”,以防您可能正在运行的web服务,因此它不是低级错误或通常返回的一般错误,而是将要使用的异常类</p>
<p>更具体地说,举个例子:</p>
<pre><code>val = int(input('Enter a number:'))
try:
val *= val
except ValueError as e:
raise e
print(val)
### ValueError will be raised if user inputs something other than a number
### this raise e will return the actual error message saying
### ValueError: invalid literal for int() with base 10: 'ok'
</code></pre>
<p>在您的情况下,您仍然可以将<code>ValueError</code>保留为要处理的异常,如下所示:</p>
<pre><code>val = int(input('Enter a number:'))
try:
val *= val
except ValueError as e:
raise ACustomException('some debug statement referring to the cause of the error')
print(val)
### now this will raise your exception class besides the ValueError exception, with a debug statement if you choose to have one in it.
</code></pre>