php - 既然所有错误都是异常，PHP7 上的 set_error_handler() 会发生什么？

Question

在 PHP5 上，同时定义 set_exception_handler() 和 set_error_handler() 非常有意义。

但是，在 PHP7 上，所有(大多数？)错误现在都是异常。那么，如果错误会由异常处理程序传递，那么定义这两个处理程序有什么意义呢？

我看到异常处理程序文档中有关于 PHP7 新 Error 类的注释，但没有提到不再有明显错误的事实，而是 Throwable，在错误处理函数中。

Since PHP 7, most errors are reported by throwing Error exceptions, which will be caught by the handler as well. Both Error and Exception implements the Throwable interface. [source]

Answer 1

Aaron Piotrowski(开发新错误异常系统的人)有一个 great blog on this .我认为你需要了解的关键点是这个

In PHP 7, an exception will be thrown when a fatal and recoverable error (E_ERROR and E_RECOVERABLE_ERROR) occurs, rather than halting script execution. Fatal errors still exist for certain conditions, such as running out of memory, and still behave as before by immediately halting script execution. An uncaught exception will also continue to be a fatal error in PHP 7. This means if an exception thrown from an error that was fatal in PHP 5.x goes uncaught, it will still be a fatal error in PHP 7.

Note that other types of errors such as warnings and notices remain unchanged in PHP 7. Only fatal and recoverable errors throw exceptions.

换句话说，考虑这个

• set_exception_handler() - 默认处理 Exception 的函数(从 PHP 7.0 开始，它可以处理所有 Throwable，因此它可以捕获可恢复的错误)
• set_error_handler() - 处理可恢复错误的函数

换句话说，它们的功能没有改变。任何在 PHP5 中触发它们的东西都会在 PHP7 中触发它们，只是现在，您可以在脚本级别使用 try-catch block 来处理特定错误。