Advanced PHP Debug Function

Mar 20, 2008 · 2 minute read
Category: php

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I have taken the debug function about as far as I can think of. This function will now take a variable and display it all in a nice easy to read format. It will also give the name of the variable being examined. It works with html, using htmlentites. It preserves the tab layout formatting for arrays making it easy to understand:

Heres How to Use It:

//For example, displaying $_POST information
dbug($_POST);

//If using inside a function
function something($blah){
dbug($blah, get_defined_vars());
}

Note that if called within the scope of a function (for example) you must give get_defined_vars().

And here are the neccessary functions

//DEbug Functions

//convert tabs to spaces
function tab2space($text){
	$text = str_replace('  ', '  ', $text);
	$text = str_replace("\t", '    ', $text);
	return $text;
}

//return name of variable passed by reference
function vname(&$var, $scope=false){
    if($scope) $vals = $scope;
    else      $vals = $GLOBALS;
    $old = $var;
	$new = 'THISONE';
	$var = $new;
	$vname = false;
    foreach($vals as $key => $val) {
		if($val !=='var'){
			if($val === $new) $vname = $key;
		}
    }
    $var = $old;
    return $vname;
  }


function dbug(&$item, $scope=false){
	$vname = vname(&$item,$scope);
	echo '<hr><h3>Debug Info: $' . $vname  . '</h3>' . tab2space(nl2br(htmlentities(var_export($item, true)))) . '<hr>';	
}