php The trigger_error function is used to create user-defined error messages. Its syntax is trigger_error(error_message,error_types). The parameter error_message is required and refers to the specified error message. The length is limited to 1024 characters.
php How to use the trigger_error function?
Definition and usage
trigger_error( ) function creates a user-defined error message.
trigger_error() function is used to trigger an error message under user-specified conditions. It can be used with the built-in error handler, or with a user-defined function set by the set_error_handler() function.
This function is useful when you need to customize the error message under a specified condition when running the script.
If an illegal error type is specified, this function returns FALSE, otherwise it returns TRUE.
Syntax
trigger_error(error_message,error_types)
Parameters
error_message Required. Specifies the error message. Length limit is 1024 characters.
error_types Optional. Specifies the error type of the error message.
Possible error types:
E_USER_ERROR - User-generated fatal error at runtime. Unrecoverable error. Stop executing the script.
E_USER_WARNING - User-generated non-fatal warning at runtime. The script did not stop executing.
E_USER_NOTICE - Default. User-generated runtime notifications. Script discovery can be a bug, but can also occur when the script is running normally.
php trigger_error function usage example
<?php $test=2; if ($test>1) { trigger_error("A custom error has been triggered"); } ?>
The output of the above code is as follows:
Notice: A custom error has been triggered in C:webfoldertest.php on line 6
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