The ? Operator in PHP / Isset inline if statements? (What exactly does this line do?)

Question

$action = isset($_GET['action']) ? $_GET['action'] : null;

Im a little unsure what the above line does? I have some vague ideas (and I know what GET does etc) but I have never come across the : "operator"(?) or the ? "operator" (?).

Thanks very much.

It's called the [ternary operator](http://php.net/manual/en/language.operators.comparison.php#language.operators.comparison.ternary) — nishantjr, Jul 05 '14 at 11:49

score 1 · Answer 1 · answered Jul 05 '14 at 11:48

1

it is a short syntax of writing

if(isset($_GET['action'])){
    $action = $_GET['action']
}else{
    $action = null;
}

That means you check a condition before ? mark, if result is true, you execute the part between ? and : But if condition check returns false, you execute the part after :

answered Jul 05 '14 at 11:48

Ali

151
11

Thanks! Surely it would already be nulled? If it wasnt set that is? – user2752347 Jul 05 '14 at 11:52
If it was not set anywhere and if you are using strict PHP mode which I will recommend while you are learning it, then trying to access a variable which is not set already will generate a warning that you are trying to access a variable that doesn't exist. The best way is to always declare a variable before using it. – Ali Jul 05 '14 at 11:58

score 0 · Answer 2 · answered Jul 05 '14 at 11:49

0

This means simply..

if(isset($_GET['action']))
   $action = $_GET['action'];
else
   $action = null;

answered Jul 05 '14 at 11:49

Deepu Sasidharan

5,193
10
40
97

The ? Operator in PHP / Isset inline if statements? (What exactly does this line do?)

2 Answers2