我把0.02美元放进去。有时，您需要在稍后的代码中添加“finally”(因为谁会在第一次就写出完美的代码呢?)在这些情况下，将try/catch放在循环之外突然变得更有意义了。例如:

try {
    for(int i = 0; i < max; i++) {
        String myString = ...;
        float myNum = Float.parseFloat(myString);
        dbConnection.update("MY_FLOATS","INDEX",i,"VALUE",myNum);
    }
} catch (NumberFormatException ex) {
    return null;
} finally {
    dbConnection.release();  // Always release DB connection, even if transaction fails.
}

因为如果出现错误，您只希望释放一次数据库连接(或选择您最喜欢的其他资源类型……)。

我想添加我自己的0.02c，关于在哪里放置异常处理的一般问题时两个相互竞争的考虑因素:

The "wider" the responsibility of the try-catch block (i.e. outside the loop in your case) means that when changing the code at some later point, you may mistakenly add a line which is handled by your existing catch block; possibly unintentionally. In your case, this is less likely because you are explicitly catching a NumberFormatException The "narrower" the responsibility of the try-catch block, the more difficult refactoring becomes. Particularly when (as in your case) you are executing a "non-local" instruction from within the catch block (the return null statement).

异常的全部意义在于鼓励第一种风格:让错误处理被合并并处理一次，而不是在每个可能的错误位置立即处理。

你应该喜欢外面的版本而不是里面的版本。这只是规则的一个特定版本，将任何可以移动到循环外的东西移动到循环外。根据IL编译器和JIT编译器的不同，您的两个版本最终可能具有不同的性能特征，也可能没有。

另一方面，你可能应该看看float。TryParse或Convert.ToFloat。

As long as you are aware of what you need to accomplish in the loop you could put the try catch outside the loop. But it is important to understand that the loop will then end as soon as the exception occurs and that may not always be what you want. This is actually a very common error in Java based software. People need to process a number of items, such as emptying a queue, and falsely rely on an outer try/catch statement handling all possible exceptions. They could also be handling only a specific exception inside the loop and not expect any other exception to occur. Then if an exception occurs that is not handled inside the loop then the loop will be "preemted", it ends possibly prematurely and the outer catch statement handles the exception.

如果循环在生活中扮演清空队列的角色，那么循环很可能在队列真正清空之前就结束了。非常常见的错误。

在你的例子中没有功能上的区别。我觉得你的第一个例子可读性更强。