check syntax

[runrunforest]

Hi,

I wonder if they are right and functioning the same ?

1/  if(isset($_SESSION['id']) && isset($_SESSION['username'])) {...}
2/  if(isset($_SESSION['id'],$_SESSION['username'])) {...}
3/  if(isset($_SESSION['id'] && $_SESSION['username'])) {...}

[fattyjules]

The first and the second ones behave exactly the same way.

The first one calls isset() twice, the second one calls isset() once, but checks for the existence of two variables.

The third one is not valid PHP - the clause passed to isset() is a value, not a variable.