Detailed introduction to the usage of error

Detailed introduction to the usage of error_reporting function in PHP

In PHP, error_reporting function is used to handle errors. The one you see most is error_reporting(E_ALL ^ E_NOTICE). What does this mean? Below we analyze the error_reporting function in detail.

Define usage

error_reporting() Sets the error reporting level of PHP and returns to the current level.

grammar

error_reporting(report_level)

If the parameter report_level is not specified, the current error level will be returned. The following are the possible values of report_level:

value	constant	describe
1	E_ERROR	Fatal runtime error. Unrecoverable error. Stop executing the script.
2	E_WARNING	Non-fatal runtime error. The execution of the script has not stopped.
4	E_PARSE	Compile-time error.
8	E_NOTICE	Runtime reminder.
16	E_CORE_ERROR	Fatal error on PHP startup. This is like an E_ERROR in PHP core
32	E_CORE_WARNING	Non-fatal error on PHP startup. This is like a warning in PHP core E_WARNING
64	E_COMPILE_ERROR	Fatal compile-time error. It's like an E_ERROR generated by the Zend script engine
128	E_COMPILE_WARNING	Non-fatal compile-time error, an E_WARNING warning generated by Zend script engine
256	E_USER_ERROR	Fatal errors that are customized by users
512	E_USER_WARNING	User-defined warning (non-fatal error)
1024	E_USER_NOTICE	User-defined reminders (often bugs, or intentional)
2048	E_STRICT	Coding standardization warning (recommended for forward compatibility)
4096	E_RECOVERABLE_ERROR	Nearly fatal runtime error, if not captured, it is considered E_ERROR
8191	E_ALL	All errors except E_STRICT

PHP does not enable errors by default, so you need configuration files:

Change display_errors = Off to display_errors = On

In addition, you need to configure the error level, because PHP defaults to display all errors, and some harmless prompts we do not need them, so the settings are as follows:

Change error_reporting = E_ALL to error_reporting = E_ALL & ~E_NOTICE

Examples for applying in PHP code:

Tip: Any number of above options can be connected with "or" (with OR or |), which can report all required errors at all levels. For example, the following code turns off user-defined errors and warnings, performs certain operations, and then returns to the original error level:

&lt;?php
 
//Disable error reporting 
error_reporting(0);
 
//Report runtime error 
error_reporting(E_ERROR | E_WARNING | E_PARSE);
 
//Report all errors 
error_reporting(E_ALL);
 
?&gt;

Learn how the error_reporting function is used, and then look at the error_reporting(E_ALL ^ E_NOTICE) code, which means to display all error messages except E_NOTICE.

Thank you for reading, I hope it can help you. Thank you for your support for this site!