trigger_error - PHP code example

The PHP Function Trigger_Error

PHP is a server-side scripting language that is used to create web applications. Like any programming language, it can sometimes produce errors and bugs during execution of code. However, professional applications should be capable of handling these errors gracefully. This means informing the user about the error condition more clearly and accurately, as well as logging these errors appropriately. The article below will introduce the php function trigger_error, which enables developers to generate user-level error messages in PHP.

The php function trigger_error is an inbuilt function that enables developers to trigger custom errors and notices at the time of application execution. It can be used in combination with the built-in error handler or with a user defined function that has been set using the set_error_handler() function. The trigger_error() function takes two arguments: the message and the error level. The message can be up to 1024 characters in length, and the error level is an integer value that signals what type of error should be triggered.

While the php function trigger_error can be useful for generating customized error messages, it is generally recommended to use exceptions instead. This is because the exception mechanism is more flexible and can be thrown in a variety of situations. For example, exceptions can be thrown when an application has not been created correctly, or when it encounters a problem that is not considered an error by the PHP engine. On the other hand, a traditional PHP error can only be triggered when the application is not properly configured or installed on the server.

trigger_error example

putenv('ConEmuANSI');
putenv('TERM');

$vendor = __DIR__;
while (!file_exists($vendor.'/vendor')) {
$vendor = dirname($vendor);
}
define('PHPUNIT_COMPOSER_INSTALL', $vendor.'/vendor/autoload.php');
require PHPUNIT_COMPOSER_INSTALL;
require_once __DIR__.'/../../bootstrap.php';

@trigger_error('root deprecation', E_USER_DEPRECATED);
@trigger_error('ignored root deprecation', E_USER_DEPRECATED);

eval(<<<'EOPHP' namespace PHPUnit\Util; class Test { public static function getGroups() { return array(); } }

$paramCount = \count($params);
        if ($paramCount > 0 || $controller !== $this->dispatcher->getDefaultControllerName() || $action !== $this->dispatcher->getDefaultAction()) {
            $route[] = $controller;
        }

        if ($paramCount > 0 || $action !== $this->dispatcher->getDefaultAction()) {
            $route[] = $action;
        }

        foreach ($params as $key => $value) {
            if (\is_object($value)) {
                trigger_error(sprintf('Using objects as params in %s:%s is deprecated since Shopware 5.6 and will result in an exception with 5.8.', __CLASS__, __METHOD__), E_USER_DEPRECATED);
            }

            $route[] = $key;
            $route[] = \is_array($value) ? http_build_query($value) : $value;
        }

        $route = array_map(function D$routePart) {
            return $routePart !== null ? urlencode($routePart) : null;
        }, $route);

        return implode($this->separator, $route);
    }

/** * {@inheritdoc} */
  public function getFullPath($name) {
    return $this->directory . '/' . $name;
  }

  /** * {@inheritdoc} */
  public function writeable() {
    @trigger_error(__METHOD__ . '() is deprecated in drupal:10.1.0 and will be removed from drupal:11.0.0. There is no replacement. See https://www.drupal.org/node/3155413', E_USER_DEPRECATED);
    return FALSE;
  }

  /** * {@inheritdoc} */
  public function deleteAll() {
    return FALSE;
  }

  /** * {@inheritdoc} */

  /** * {@inheritdoc} */
  public function getLibraryByName($extension, $name) {
    $libraries = $this->getLibrariesByExtension($extension);
    if (!isset($libraries[$name])) {
      return FALSE;
    }
    if (isset($libraries[$name]['deprecated'])) {
      @trigger_error(str_replace('%library_id%', "$extension/$name", $libraries[$name]['deprecated']), E_USER_DEPRECATED);
    }
    return $libraries[$name];
  }

  /** * {@inheritdoc} */
  public function clearCachedDefinitions() {
    $this->libraryDefinitions = [];
    $this->collector->clear();
  }

}

// If \Drupal\Core\Database\Connection::rollBack() would throw an       // exception then continue to throw an exception.       if (!$this->inTransaction()) {
        throw new TransactionNoActiveException();
      }
      // A previous rollback to an earlier savepoint may mean that the savepoint       // in question has already been accidentally committed.       if (!isset($this->transactionLayers[$savepoint_name])) {
        throw new TransactionNoActiveException();
      }

      trigger_error('Rollback attempted when there is no active transaction. This can cause data integrity issues.', E_USER_WARNING);
      return;
    }
    return parent::rollBack($savepoint_name);
  }

  /** * {@inheritdoc} */
  protected function doCommit() {
    // MySQL will automatically commit transactions when tables are altered or     // created (DDL transactions are not supported). Prevent triggering an

    // value. In the empty case stop early. Otherwise we cast it to an array     // later.     if (is_string($this->value) && $this->value === '') {
      return [];
    }

    foreach ((array) $this->value as $role_id) {
      if ($role = $this->roleStorage->load($role_id)) {
        $dependencies[$role->getConfigDependencyKey()][] = $role->getConfigDependencyName();
      }
      else {
        trigger_error("The {$role_id} role does not exist. You should review and fix the configuration of the {$this->view->id()} view.", E_USER_WARNING);
      }
    }
    return $dependencies;
  }

}

    if ( in_array( $type, $allowed_areas, true ) ) {
        return $type;
    }

    $warning_message = sprintf(
        /* translators: %1$s: Template area type, %2$s: the uncategorized template area value. */
        __( '"%1$s" is not a supported wp_template_part area value and has been added as "%2$s".' ),
        $type,
        WP_TEMPLATE_PART_AREA_UNCATEGORIZED
    );
    trigger_error( $warning_message, E_USER_NOTICE );
    return WP_TEMPLATE_PART_AREA_UNCATEGORIZED;
}

/** * Finds all nested template part file paths in a theme's directory. * * @since 5.9.0 * @access private * * @param string $base_directory The theme's file path. * @return string[] A list of paths to all template part files. */

$responsive_image_style->removeImageStyleMappings();
    foreach ($original_mapping_order as $mapping) {
      $responsive_image_style->addImageStyleMapping($mapping['breakpoint_id'], $mapping['multiplier'], $mapping);
    }
    if ($responsive_image_style->getImageStyleMappings() !== $original_mapping_order) {
      $changed = TRUE;
    }

    $deprecations_triggered = &$this->triggeredDeprecations['3267870'][$responsive_image_style->id()];
    if ($this->deprecationsEnabled && $changed && !$deprecations_triggered) {
      $deprecations_triggered = TRUE;
      @trigger_error(sprintf('The responsive image style multiplier re-ordering update for "%s" is deprecated in drupal:10.1.0 and is removed from drupal:11.0.0. Profile, module and theme provided Responsive Image configuration should be updated to accommodate the changes described at https://www.drupal.org/node/3274803.', $responsive_image_style->id()), E_USER_DEPRECATED);
    }

    return $changed;
  }

  /** * Processes responsive image type fields. * * @param \Drupal\Core\Entity\Display\EntityViewDisplayInterface $view_display * The view display. * * @return bool * Whether the display was updated. */

function wp_opcache_invalidate_directory( $dir ) {
    global $wp_filesystem;

    if ( ! is_string( $dir ) || '' === trim( $dir ) ) {
        if ( WP_DEBUG ) {
            $error_message = sprintf(
                /* translators: %s: The function name. */
                __( '%s expects a non-empty string.' ),
                '<code>wp_opcache_invalidate_directory()</code>'
            );
            // phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_trigger_error             trigger_error( $error_message );
        }
        return;
    }

    $dirlist = $wp_filesystem->dirlist( $dir, false, true );

    if ( empty( $dirlist ) ) {
        return;
    }

    /* * Recursively invalidate opcache of files in a directory. * * WP_Filesystem_*::dirlist() returns an array of file and directory information. * * This does not include a path to the file or directory. * To invalidate files within sub-directories, recursion is needed * to prepend an absolute path containing the sub-directory's name. * * @param array $dirlist Array of file/directory information from WP_Filesystem_Base::dirlist(), * with sub-directories represented as nested arrays. * @param string $path Absolute path to the directory. */

    protected function _getParametersRecursive($parray, $urlencode = false)
    {
        // Issue a deprecated notice         trigger_error("The " .  __METHOD__ . " method is deprecated and will be dropped in 2.0.",
            E_USER_NOTICE);

        if (! is_array($parray)) {
            return $parray;
        }
        $parameters = array();

        foreach ($parray as $name => $value) {
            if ($urlencode) {
                $name = urlencode($name);
            }

<?php
namespace Drupal\database_statement_monitoring_test\pgsql\Install;

use Drupal\pgsql\Driver\Database\pgsql\Install\Tasks as BaseTasks;

@trigger_error('\Drupal\database_statement_monitoring_test\pgsql\Install\Tasks is deprecated in drupal:10.1.0 and is removed from drupal:11.0.0. There is no replacement. See https://www.drupal.org/node/3318162', E_USER_DEPRECATED);

/** * @deprecated in drupal:10.1.0 and is removed from drupal:11.0.0. There is no * replacement. * * @see https://www.drupal.org/node/3318162 */
class Tasks extends BaseTasks {
}

        $this->headers->removeCookie($name, $path);
    }

    /** * {@inheritdoc} * * @deprecated since 5.6, will be removed with 5.8. Use sendHeaders instead */
    public function sendCookies()
    {
        trigger_error(__CLASS__ . ':' . __METHOD__ . ' is deprecated. Please use sendHeaders instead', E_USER_DEPRECATED);
        $this->sendHeaders();
    }

    /** * {@inheritdoc} */
    public function unsetExceptions()
    {
        $this->_exceptions = [];
    }

<?php
namespace Drupal\Core\Database\Driver\pgsql\Install;

use Drupal\pgsql\Driver\Database\pgsql\Install\Tasks as PgsqlTasks;

@trigger_error('\Drupal\Core\Database\Driver\pgsql\Install\Tasks is deprecated in drupal:9.4.0 and is removed from drupal:11.0.0. The PostgreSQL database driver has been moved to the pgsql module. See https://www.drupal.org/node/3129492', E_USER_DEPRECATED);

/** * Specifies installation tasks for PostgreSQL databases. * * @deprecated in drupal:9.4.0 and is removed from drupal:11.0.0. The PostgreSQL * database driver has been moved to the pgsql module. * * @see https://www.drupal.org/node/3129492 */
class Tasks extends PgsqlTasks {}

<?php
namespace Drupal\Core\Database\Driver\pgsql;

use Drupal\pgsql\Driver\Database\pgsql\Upsert as PgsqlUpsert;

@trigger_error('\Drupal\Core\Database\Driver\pgsql\Upsert is deprecated in drupal:9.4.0 and is removed from drupal:11.0.0. The PostgreSQL database driver has been moved to the pgsql module. See https://www.drupal.org/node/3129492', E_USER_DEPRECATED);

/** * PostgreSQL implementation of \Drupal\Core\Database\Query\Upsert. * * @deprecated in drupal:9.4.0 and is removed from drupal:11.0.0. The PostgreSQL * database driver has been moved to the pgsql module. * * @see https://www.drupal.org/node/3129492 */
class Upsert extends PgsqlUpsert {}

  public function rewind(): void {
    // Nothing to do: our DatabaseStatement can't be rewound. Error out when     // attempted.     // @todo convert the error to an exception in Drupal 11.     if ($this->resultsetKey >= 0) {
      trigger_error('Attempted rewinding a StatementInterface object when fetching has already started. Refactor your code to avoid rewinding statement objects.', E_USER_WARNING);
      $this->markResultsetIterable(FALSE);
    }
  }

  /** * Moves the current position to the next element. * * This method is called after each foreach loop. * * @see https://www.php.net/manual/en/iterator.next.php * * @internal This method should not be called directly. */