Undefined Offset received using error_reporting(E_ALL)

slightlyeskew

Hey All!

As per Halo's advice, I've started using error_reporting(E_ALL) in my scripts. I've recently received an "Undefined Offset" warning. What is that?

johanafm

Sounds like an out of bounds string index.

$str = '012';
echo $str[2];	// 2
echo $str[3];	// undefined offset

bradgrafelman

Or trying to use data from external variables without first checking to see if that data exists. For example, you should never use any of the following:

$foo = $_POST['foo']; // or $_GET, $_SESSION, $_COOKIE, et. al.

if($_POST['submit']) {
    // ...
}

echo "Why hello there, $_POST[foo]!";

// etc. etc.