PHP: Simple PHP error handler with extra features.

ErrorHandler.class.php

<?php

/*
	ErrorHandler Class
	By James King
	v0.1 Alpha

	WARNING: This class is still in ALPHA phase. Not recommended for production.
	
	Manages and handles any PHP errors found in your script.
	
	Features
	- Debug configuration to show full error contents or a pretty message.
	- Mute configuration to completely mute all errors.
	- Technical Email configuration to have emails sent out upon error.
	- Error Level configuration for error levels of when to email the technical email.
	- Editable friendly message to show if mute is off and debug is off.

	Future Features
	(none yet)
*/

/**
* ErrorHandler Class - Manages and Handles all PHP errors.
*/
class ErrorHandler
{
	private $debug = false; // Debug mode. True to show full PHP error, false to show prettier error text.
	private $mute = false; // Set to true to hide all errors, false for default error class action.
	private $technicalEmail; // Technical email to send all errors to. (Blank/false/NULL for don't send errors)
	public $friendlyMsg = "Sorry, an error has occured. Please contact your system administrator."; // Friendly HTML error message shown if debug is off and mute is off. Override this manually.
	public $sendEmail = array(E_ERROR, E_USER_ERROR, E_USER_WARNING, E_WARNING); // Array of error levels which require an email to be sent.

	/**
	 * ErrorHandler class construction. Registers self as error handler for the entire session and checks config.
	 * @param boolean $debug          Whether debug mode is on or off. (Default false)
	 * @param boolean $mute           Whether to mute all errors. (Default false)
	 * @param string  $technicalEmail Email Address of where to send errors. (Default null)
	 */
	function __construct($debug=false, $mute=false, $technicalEmail=null)
	{
		if($debug == true)
			$this->debug = true;
		if($mute == true)
			$this->mute = true;
		if(strpos($technicalEmail, '@'))
			$this->technicalEmail = $technicalEmail;

		set_error_handler(array($this, 'handleError'));
	}

	/**
	 * Base error handling abilites. Must not be invoked directly.
	 * @param  int    $errno   Error number. (can be a PHP Error level constant)
	 * @param  string $errstr  Error description.
	 * @param  string $errfile File in which the error occurs.
	 * @param  int    $errline Line number where the error is situated.
	 */
	private function handleError($errno, $errstr, $errfile=false, $errline=false)
	{
		$errorString = " [$errno] ".$errstr;
		if($errfile)
			$errorString = $errorString . " [F:".$errfile."]";
		if($errline)
			$errorString = $errorString . " [L:".$errline."]";
		$errorString = $errorString . "</pre><br />";

		switch($errno)
		{
			case E_USER_ERROR:
			case E_ERROR:
				if(!$this->mute)
				{
					if($this->debug)
						echo "<pre>FATAL</b>".$errorString;
					else
						echo $this->friendlyMsg;
					exit;
				}
				break;
			case E_USER_WARNING:
			case E_WARNING:
				if(!$this->mute)
				{
					if($this->debug)
						echo "<pre>WARNING</b>".$errorString;
					else
						echo $this->friendlyMsg;
				}
				break;
			case E_NOTICE:
			case E_USER_NOTICE:
				if(!$this->mute)
				{
					if($this->debug)
						echo "<pre>NOTICE</b>".$errorString;
				}
				break;

				/*
					Add your own error cases here!
				*/
				
			default:
				// Do nothing for any other errors.
				break;
		}

		if(in_array($errno, $this->sendEmail))
			$this->sendTechnicalEmail($errno, $errstr, $errfile, $errline);
	}

	/**
	 * Trigger a custom error through this error handler.
	 * @param  string $msg  Your custom error message
	 * @param  string $type Type of error (FATAL, ERROR, WARNING or NOTICE) (Anything else is treated as WARNING) (Default null)
	 */
	public function triggerError($msg, string $type=null)
	{
		$type = strtoupper($type);
		switch ($type) {
			case 'FATAL':
			case 'ERROR':
				$type = E_USER_ERROR;
				break;
			case 'WARNING':
			default:
				$type = E_USER_WARNING;
				break;
			case 'NOTICE':
				$type = E_USER_NOTICE;
				break;
		}

		$this->handleError($type, $msg);
	}

	public function sendTechnicalEmail($errno, $errstr, $errfile=false, $errline=false)
	{
		if(strpos($this->technicalEmail, '@'))
		{
			$message = "Your website has generated an unexpected error:

No: $errno";
			if($errfile)
				$message = $message . "
File: $errfile";
			if($errline)
				$message = $message . "
Line: $errline";

			$message = $message . "

Error: $errstr";

			// Add an @ to stop inception.
			$send = @mail($this->technicalEmail, "Error on your website", $message, "From: NoReply@ErrorHandler");
		}
	}
}

?>

Nice class, thank you. I tried a simple division by zero and encountered following error:

Warning: Invalid callback ErrorHandler::handleError, cannot access private method ErrorHandler::handleError() in C:\Progs\Dev\wamp64\www\error\index.php on line 29

changing the scope from private to public resolves this, but i don't think that you made such a mistake.
Maybe you could take a look at it.

You can handle FATAL errors by using register_shutdown_function() and error_get_last().