因为下一个问题是“我已经捕获了一个异常，接下来我该做什么?”你会怎么做?如果你什么都不做——这是错误隐藏，程序可能“就是不能工作”，没有任何机会发现发生了什么。您需要了解捕获异常后要做什么，并且只有在知道的情况下才进行捕获。

Herb Sutter在这里写过这个问题。绝对值得一读。 摘要:

"Writing exception-safe code is fundamentally about writing 'try' and 'catch' in the correct places." Discuss. Put bluntly, that statement reflects a fundamental misunderstanding of exception safety. Exceptions are just another form of error reporting, and we certainly know that writing error-safe code is not just about where to check return codes and handle error conditions. Actually, it turns out that exception safety is rarely about writing 'try' and 'catch' -- and the more rarely the better. Also, never forget that exception safety affects a piece of code's design; it is never just an afterthought that can be retrofitted with a few extra catch statements as if for seasoning.

如果您想测试每个函数的结果，请使用返回码。

exception的目的是为了降低测试结果的频率。其思想是将异常(不寻常的，罕见的)条件从更普通的代码中分离出来。这使得普通代码更简洁，但仍然能够处理那些异常情况。

在设计良好的代码中，较深的函数可能会抛出，较高级的函数可能会捕获。但关键是，许多“介于两者之间”的功能将完全摆脱处理异常情况的负担。它们只需要是“异常安全的”，这并不意味着它们必须捕获。

除了上面的建议，我个人使用尝试+抓+扔的方法;原因如下:

At boundary of different coder, I use try + catch + throw in the code written by myself, before the exception being thrown to the caller which is written by others, this gives me a chance to know some error condition occured in my code, and this place is much closer to the code which initially throw the exception, the closer, the easier to find the reason. At the boundary of modules, although different module may be written my same person. Learning + Debug purpose, in this case I use catch(...) in C++ and catch(Exception ex) in C#, for C++, the standard library does not throw too many exception, so this case is rare in C++. But common place in C#, C# has a huge library and an mature exception hierarchy, the C# library code throw tons of exception, in theory I(and you) should know every exceptions from the function you called, and know the reason/case why these exception being thrown, and know how to handle them(pass by or catch and handle it in-place)gracefully. Unfortunately in reality it's very hard to know everything about the potential exceptions before I write one line of code. So I catch all and let my code speak aloud by logging(in product environment)/assert dialog(in development environment) when any exception really occurs. By this way I add exception handling code progressively. I know it conflit with good advice but in reality it works for me and I don't know any better way for this problem.

因为下一个问题是“我已经捕获了一个异常，接下来我该做什么?”你会怎么做?如果你什么都不做——这是错误隐藏，程序可能“就是不能工作”，没有任何机会发现发生了什么。您需要了解捕获异常后要做什么，并且只有在知道的情况下才进行捕获。

我想在这个讨论中补充一点，自从c++ 11以来，它确实很有意义，只要每个catch块重新抛出异常，直到它可以/应该被处理为止。通过这种方式可以生成反向跟踪。因此，我认为前面的观点在某种程度上已经过时了。

使用std::nested_exception和std::throw_with_nested

在这里和这里的StackOverflow描述了如何实现这一点。

由于可以对任何派生异常类执行此操作，因此可以向这样的回溯添加大量信息! 你也可以看看我在GitHub上的MWE，在那里回溯看起来是这样的:

Library API: Exception caught in function 'api_function'
Backtrace:
~/Git/mwe-cpp-exception/src/detail/Library.cpp:17 : library_function failed
~/Git/mwe-cpp-exception/src/detail/Library.cpp:13 : could not open file "nonexistent.txt"