Unlike other programming languages that throw exceptions when encountering errors, PHP also has an exception mechanism when handling objects, but PHP will perform as happily as possible and ignore what happened, unless it encounters an extremely serious error. There is an exception. This article outlines PHP-related error exception handling mechanisms.
PHP has several error severity levels. The three most common types of information are errors, notices, and warnings. They have different severity: E_ERROR, E_NOTICE and E_WARNING. The error is a serious problem during operation, usually caused by code error, it must be corrected, otherwise PHP will stop execution. Notifications are information of a recommended nature, because the program code may cause problems during execution, but the program will not stop. The warning is a non-fatal error, and program execution will not be aborted.