Link the debug information of PHP with the Firefox Console

I learned a trick today, that is, if it is in Firefox or chrome, you can send the warning, error, and other information in PHP,

Output to the firebug console in different categories.

First, there is a debug class as follows:

class PHPDebug {function __construct() {    if (!defined("LOG"))    define("LOG",1);    if (!defined("INFO"))   define("INFO",2);    if (!defined("WARN"))   define("WARN",3);    if (!defined("ERROR"))  define("ERROR",4);    define("NL","\r\n");    echo '<script type="text/javascript">'.NL;    /// this is for IE and other browsers w/o console    echo 'if (!window.console) console = {};';    echo 'console.log = console.log || function(){};';    echo 'console.warn = console.warn || function(){};';    echo 'console.error = console.error || function(){};';    echo 'console.info = console.info || function(){};';    echo 'console.debug = console.debug || function(){};';    echo '</script>';    /// end of IE}function debug($name, $var = null, $type = LOG) {    echo '<script type="text/javascript">'.NL;    switch($type) {        case LOG:            echo 'console.log("'.$name.'");'.NL;        break;        case INFO:            echo 'console.info("'.$name.'");'.NL;        break;        case WARN:            echo 'console.warn("'.$name.'");'.NL;        break;        case ERROR:            echo 'console.error("'.$name.'");'.NL;        break;    }    if (!empty($var)) {        if (is_object($var) || is_array($var)) {            $object = json_encode($var);            echo 'var object'.preg_replace('~[^A-Z|0-9]~i',"_",$name).' = \''.str_replace("'","\'",$object).'\';'.NL;            echo 'var val'.preg_replace('~[^A-Z|0-9]~i',"_",$name).' = eval("(" + object'.preg_replace('~[^A-Z|0-9]~i',"_",$name).' + ")" );'.NL;            switch($type) {                case LOG:                    echo 'console.debug(val'.preg_replace('~[^A-Z|0-9]~i',"_",$name).');'.NL;                break;                case INFO:                    echo 'console.info(val'.preg_replace('~[^A-Z|0-9]~i',"_",$name).');'.NL;                break;                case WARN:                    echo 'console.warn(val'.preg_replace('~[^A-Z|0-9]~i',"_",$name).');'.NL;                break;                case ERROR:                    echo 'console.error(val'.preg_replace('~[^A-Z|0-9]~i',"_",$name).');'.NL;                break;            }        } else {            switch($type) {                case LOG:                    echo 'console.debug("'.str_replace('"','\\"',$var).'");'.NL;                break;                case INFO:                    echo 'console.info("'.str_replace('"','\\"',$var).'");'.NL;                break;                case WARN:                    echo 'console.warn("'.str_replace('"','\\"',$var).'");'.NL;                break;                case ERROR:                    echo 'console.error("'.str_replace('"','\\"',$var).'");'.NL;                break;            }        }    }    echo '</script>'.NL;}}

It is easy to use, as shown in the following example:

// include and instantiate the class    require_once("PHPDebug.php");    $debug = new PHPDebug();    // simple message to console    $debug->debug("A very simple message");    // vaiable to console    $x = 3;    $y = 5;    $z = $x/$y;    $debug->debug("Variable Z: ", $z);    // a warnign    $debug->debug("A simple Warning", null, WARN);    // info    $debug->debug("A simple Info message", null, INFO);    // An error    $debug->debug("A simple error messsage", null, ERROR);    // Array in console    $fruits = array("banana", "apple", "strawberry", "pineaple");    $fruits = array_reverse($fruits);    $debug->debug("Fruits array", $fruits);    // object to console    $book               = new stdClass;    $book->title        = "Harry Potter and the Prisoner of Azkaban";    $book->author       = "J. K. Rowling";    $book->publisher    = "Arthur A. Levine Books";    $book->amazon_link  = "http://www.amazon.com/dp/0439136369/";    $debug->debug("Object", $book);

In this way, you can display various warnings or errors in different categories on the browser console.