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trigger_error

(PHP 4 >= 4.0.1, PHP 5, PHP 7, PHP 8)

trigger_errorDéclenche une erreur utilisateur

Description

trigger_error(string $message, int $error_level = E_USER_NOTICE): true

trigger_error() est utilisé pour déclencher une erreur utilisateur. Elle peut aussi être utilisée en conjonction avec un gestionnaire d'erreurs interne, ou un gestionnaire d'erreurs utilisateur qui a été choisi comme gestionnaire d'erreurs avec set_error_handler().

trigger_error() est pratique lorsque vous devez générer une réponse particulière lors de l'exécution.

Liste de paramètres

message

Le message d'erreur désigné pour cette erreur. Il est limité en longueur à 1024 octets. Tous caractères après les 1024 octets seront ignorés.

error_level

Le type d'erreur désigné pour cette erreur. Cela ne fonctionne qu'avec la famille de constantes E_USER et sera par défaut E_USER_NOTICE.

Valeurs de retour

Retourne toujours true.

Erreurs / Exceptions

Cette fonction lance une ValueError si le error_level n'est pas l'un des E_USER_ERROR, E_USER_WARNING, E_USER_NOTICE, E_USER_DEPRECATED.

Historique

Version Description
8.0.0 La fonction lance désormais une ValueError si un error_level invalide est spécifié. Auparavant, elle retournait false.

Exemples

Exemple #1 Exemple avec trigger_error()

Voir set_error_handler() pour un exemple plus conséquent.

<?php
if ($divisor == 0) {
trigger_error("Impossible de diviser par zéro", E_USER_ERROR);
}
?>

Notes

Avertissement

Les entités HTML contenues dans le paramètre message ne sont pas échappées. Utilisez la fonction htmlentities() sur le message si l'erreur doit être affichée dans un navigateur.

Voir aussi

add a note

User Contributed Notes 5 notes

up
52
someone at attbi dot com
21 years ago
the idea is never to give out file names, line numbers, and cryptic codes to the user. Use trigger_error() after you used set_error_handler() to register your own callback function which either logs or emails the error codes to you, and echo a simple friendly message to the user.

And turn on a more verbose error handler function when you need to debug your scripts. In my init.php scripts I always have:

if (_DEBUG_) {
set_error_handler ('debug_error_handler');
}
else {
set_error_handler ('nice_error_handler');
}
up
16
Howard Yeend
14 years ago
trigger_error always reports the line and file that trigger_error was called on. Which isn't very useful.

eg:

main.php:
<?php
include('functions.php');
$x = 'test';
doFunction($x);
?>

functions.php:
<?php
function doFunction($var) {
if(
is_numeric($var)) {
/* do some stuff*/
} else {
trigger_error('var must be numeric');
}
}
?>

will output "Notice: var must be numeric in functions.php on line 6"
whereas "Notice: var must be numeric in main.php on line 4" would be more useful

here's a function to do that:

<?php

function error($message, $level=E_USER_NOTICE) {
$caller = next(debug_backtrace());
trigger_error($message.' in <strong>'.$caller['function'].'</strong> called from <strong>'.$caller['file'].'</strong> on line <strong>'.$caller['line'].'</strong>'."\n<br />error handler", $level);
}
?>

So now in our example:

main.php:
<?php
include('functions.php');
$x = 'test';
doFunction($x);
?>

functions.php:
<?php
function doFunction($var) {
if(
is_numeric($var)) {
/* do some stuff*/
} else {
error('var must be numeric');
}
}

function
error($message, $level=E_USER_NOTICE) {
$caller = next(debug_backtrace());
trigger_error($message.' in <strong>'.$caller['function'].'</strong> called from <strong>'.$caller['file'].'</strong> on line <strong>'.$caller['line'].'</strong>'."\n<br />error handler", $level);
}
?>

now outputs:

"Notice: var must be numeric in doFunction called from main.php on line 4"
up
8
richard at 2006 dot atterer dot net
18 years ago
Beware, trigger_error() is absolutely useless for transporting your own function's error messages in $php_errormsg:

ini_set('track_errors', TRUE);
function x() { trigger_error('MY ERROR'); }
@x();
echo "Error 1: \\"$php_errormsg\\"\\n";
@file_get_contents('/nonexisting');
echo "Error 2: \\"$php_errormsg\\"\\n";

This outputs:

Error 1: ""
Error 2: "failed to open stream: No such file or directory"

This behaviour is consistent with the description of $php_errormsg, which says that the variable will only be available within the scope in which the error occurred. The problem can be worked around with a custom error handler like the one below. However, I'm undecided whether changing the language in this way is good:

function errHandler($errno, $errstr, $errfile, $errline) {
global $php_errormsg; $php_errormsg = $errstr;
}
set_error_handler('errHandler');
up
5
aydin dot kn12 at gmail dot com
9 years ago
If error_type is E_USER_ERROR then trigger_error throw FATAL ERROR and script stopped after this line.

<?php

$msg
= 'This is the test message for echo';

trigger_error('Error message', E_USER_ERROR); // Script stopped after this line...

echo $msg; // This line does not appear...

?>
up
4
PhpMyCoder
13 years ago
For those of you looking to use your own file or line number in the error (possibly using debug_backtrace()) instead of the ones created by trigger_error(), here is a solution:
Create a custom function to handle E_USER_ERRORs that simply outputs the error type and message, while excluding the line number and file trigger_error() reports. You may also configure it to handle user warnings and notices if necessary (I did in the example below).

<?php
function error_handler($level, $message, $file, $line, $context) {
//Handle user errors, warnings, and notices ourself
if($level === E_USER_ERROR || $level === E_USER_WARNING || $level === E_USER_NOTICE) {
echo
'<strong>Error:</strong> '.$message;
return(
true); //And prevent the PHP error handler from continuing
}
return(
false); //Otherwise, use PHP's error handler
}

function
trigger_my_error($message, $level) {
//Get the caller of the calling function and details about it
$callee = next(debug_backtrace());
//Trigger appropriate error
trigger_error($message.' in <strong>'.$callee['file'].'</strong> on line <strong>'.$callee['line'].'</strong>', $level);
}

//Use our custom handler
set_error_handler('error_handler');

//-------------------------------
//Demo usage:
//-------------------------------
function abc($str) {
if(!
is_string($str)) {
trigger_my_error('abc() expects parameter 1 to be a string', E_USER_ERROR);
}
}

abc('Hello world!'); //Works
abc(18); //Error: abc() expects parameter 1 to be a string in [FILE].php on line 31
?>

This is a pretty simple concept and I'm sure most of you know this, but for those that don't, let it serve as a good example!
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