跳过循环中的错误？ （PHP）
我有一个循环，代码循环，在每个循环中它连接到不同的服务器，然后进行 MySQL 查询。然而，有时循环/查询之一无法到达末尾，并且所有代码都会中断。有没有办法，如果循环出现错误，则跳过进程/移至下一个循环？
I have a loop where the code loops and in every loop it connects to different server and then makes MySQL query. However sometimes one of the loops/queries cannot reach to the end and all the code breaks. Is there a way where if the loop gives error then skip the processes / move to next loop?
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正如上面的评论所述，执行此操作的正确方法是在
try...catch块中。要了解有关这些内容的更多信息，您可以在此处阅读相关内容。
谢谢@保罗。
As stated in the comments above, the correct way to do this is within a
try...catchblock.To learn more about these, you can read about them here.
Thanks @Paul.
在该循环内，检查连接，如果已建立，则执行逻辑。因此，如果没有建立连接，逻辑部分将被跳过。
Inside that loop ,check the connection and if it is made, do the logic. So that if connection is not made, the logic part would be skipped.
使用“继续”跳到循环中的下一项：
继续
Use "continue" to skip to the next item in hte loop:
continue
这一切都取决于您是否使用 php 的内置 mysql、mysqli 或某些第三方库。但作为一般规则，我会推荐以下逻辑。
根据您在相关表上所做的工作，您还可以使用 @ 前缀（例如 @mysql_query）来抑制查询中的任何错误然后检查受影响的行数。如果你进行选择，你可以检查你的结果集，看看你是否得到了任何返回等。不过，我不喜欢使用 @ ，应该注意的是，从现有表中进行选择为空，类似的情况可能会导致奇怪的行为，具体取决于您的代码。 Try/Catch 是处理错误控制流的更好方法。但相比之下，实际上抛出异常是一个相当慢的过程，并且由于所有工作都围绕着连接到各处的数据库，因此如果此循环可能抛出大量异常，那么进一步减慢速度可能不是一个好主意。此外，当使用它跳过循环中的某个步骤时，某些人可能很难遵循逻辑。因此，像 @ 这样的东西在这里是可以接受的;)
This all depends on if you use php's built-in mysql, mysqli or some third party library. But as a general rule I would recommend the following logic.
Depending on the work you do on the table in question you could also suppress any errors from your query using the @ prefix like @mysql_query and then check for number of affected rows. If you do a select you could check your result set to see if you got anything back etc. I don't like the use of @ though and it should be noted that a select from an existing table that was empty and similar situations could result in strange behavior depending on your code. Try/Catch is a nicer approach to handle error control flow. But actually throwing an exception is quite a slow process in comparison and since all the work revolves around connecting to databases all over the place it might not be a good idea to slow it down even more if a lot of exceptions could be thrown by this loop. Also, when using it to skip a step in a loop it can be quite hard for some people to follow the logic. Therefore something like @ could be acceptable here ;)