"? $_SESSION['username'] : NULL"?

Question

can you guys help me?

I have these codes here,

$sUsername = isset($_SESSION['username']) ? $_SESSION['username'] : NULL;

what I want to ask is what does the ? $_SESSION['username'] : NULL; mean?

does it mean that it checks whether the session is null or not? I'm sorry but this is my first time seeing these codes so I'd really appreciate if someone can explain it to me or give me reference sites about this.

According to php.net, isset — Determines if a variable is set and is not NULL, — Mawia HL, Sep 13 '15 at 02:15
sorry if this question has been asked before. and thank you. :0 — Indra, Oct 28 '15 at 00:18

score 1 · Answer 1 · edited May 23 '17 at 11:58

1

Just for you:

$sUsername = isset($_SESSION['username']) ? $_SESSION['username'] : NULL;

means

if (isset($_SESSION['username'])) {
    $sUsername = $_SESSION['username'];
}
else {
    $sUsername = NULL;
}

Check this: How do I use shorthand if / else?

edited May 23 '17 at 11:58

Community

1
1

answered Sep 13 '15 at 02:23

csklrnd

184
8

score 1 · Answer 2 · answered Sep 13 '15 at 02:26

"?:" is known as the "Ternary Operator" ... it's shorthand for if/else

$sUsername = isset( $_SESSION['username'] ) ? $_SESSION['username'] : NULL ;

is equivalent to:

if( isset($_SESSION['username']) ){
    $sUsername = $_SESSION['username'];
} else {
    $sUsername = NULL;
}

"? $_SESSION['username'] : NULL"?

2 Answers2