set_error_handler

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

set_error_handler - Sets a user-defined error handler function

Code Examples

Example #1 Error handling with set_error_handler and trigger_error

Result: vector a Array ( [0] => 2 [1] => 3 [2] => foo [3] => 5.5 [4] => 43.3 [5] => 21.11 ) ---- vector b - a notice (b = log(PI) * a) My NOTICE [1024] Value at position 2 is not a number, using 0 (zero) Array ( [0] => 2.2894597716988 [1] => 3.4341896575482 [2] => 0 [3] => 6.2960143721717 [4] => 49.566804057279 [5] => 24.165247890281 ) ---- vector c - a warning My WARNING [512] Incorrect input vector, array of values expected NULL ---- vector d - fatal error My ERROR [256] log(x) for x <= 0 is undefined, you used: scale = -2.5 Fatal error on line 35 in file trigger_error.php, PHP 5.2.1 (FreeBSD) Aborting...

<?php
// error handler function
function myErrorHandler($errno, $errstr, $errfile, $errline)
{
 if (!(error_reporting() & $errno)) {
 // This error code is not included in error_reporting, so let it fall
 // through to the standard PHP error handler
 return false;
 }
 // $errstr may need to be escaped:
 $errstr = htmlspecialchars($errstr);
 switch ($errno) {
 case E_USER_ERROR:
 echo "My ERROR [$errno] $errstr \n";
 echo " Fatal error on line $errline in file $errfile";
 echo ", PHP " . PHP_VERSION . " (" . PHP_OS . ") \n";
 echo "Aborting... \n";
 exit(1);
 case E_USER_WARNING:
 echo "My WARNING [$errno] $errstr \n";
 break;
 case E_USER_NOTICE:
 echo "My NOTICE [$errno] $errstr \n";
 break;
 default:
 echo "Unknown error type: [$errno] $errstr \n";
 break;
 }
 /* Don't execute PHP internal error handler */
 return true;
}
// function to test the error handling
function scale_by_log($vect, $scale)
{
 if (!is_numeric($scale) || $scale <= 0) {
 trigger_error("log(x) for x <= 0 is undefined, you used: scale = $scale", E_USER_ERROR);
 }
 if (!is_array($vect)) {
 trigger_error("Incorrect input vector, array of values expected", E_USER_WARNING);
 return null;
 }
 $temp = array();
 foreach($vect as $pos => $value) {
 if (!is_numeric($value)) {
 trigger_error("Value at position $pos is not a number, using 0 (zero)", E_USER_NOTICE);
 $value = 0;
 }
 $temp[$pos] = log($scale) * $value;
 }
 return $temp;
}
// set to the user defined error handler
$old_error_handler = set_error_handler("myErrorHandler");
// trigger some errors, first define a mixed array with a non-numeric item
echo "vector a\n";
$a = array(2, 3, "foo", 5.5, 43.3, 21.11);
print_r($a);
// now generate second array
echo "----\nvector b - a notice (b = log(PI) * a)\n";
/* Value at position $pos is not a number, using 0 (zero) */
$b = scale_by_log($a, M_PI);
print_r($b);
// this is trouble, we pass a string instead of an array
echo "----\nvector c - a warning\n";
/* Incorrect input vector, array of values expected */
$c = scale_by_log("not array", 2.3);
var_dump($c); // NULL
// this is a critical error, log of zero or negative number is undefined
echo "----\nvector d - fatal error\n";
/* log(x) for x <= 0 is undefined, you used: scale = $scale" */
$d = scale_by_log($a, -2.5);
var_dump($d); // Never reached

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set_error_handler

Example #1 Error handling with set_error_handler and trigger_error

Function set_error_handler:

Error Handling and Logging Functions

Most used PHP functions