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PHP

Posted by Andrew Chappell
Andrew Chappell
12,782 Points

What does this mean in PHP?

if(isset($events[$event_day])

I know it is checking if it is set but what exactly is $events[$event_day]? Is it an array and a key?

3 Answers

Joakim Bergman
Joakim Bergman
14,501 Points
Joakim Bergman
Joakim Bergman
14,501 Points

It seems to be, You can always do a var_dump($events[$event_day]); then you'll see the datatype printed to the screen along with other info.

Andrew Chappell
Andrew Chappell
12,782 Points

I did the var_dump and it returned about 30 results of NULL so it must be an array. Thanks.

Kyle Germaine
Kyle Germaine
8,174 Points
Kyle Germaine
Kyle Germaine
8,174 Points

isset is a boolean function (produces either True or False response) that determines if a variable has been set or not. If the events variable has a value set to it, it will execute the code in the curly brackets following. You would normally use it in conjunction with an IF/ELSE statement like...

if(isset($events[$event_day]) {
          echo " 'events' array has 'event_day' value set to it";
} else {
          echo " 'events' array doesn't have an  'event_day' value set to it";
}

I'm still a newbie and pretty sure this isn't the best way to describe it, but here is a pretty good non-technical explanation (http://kunststube.net/isset/).

Kyle Germaine
Kyle Germaine
8,174 Points
Kyle Germaine
Kyle Germaine
8,174 Points

Haha, oops should have actually read your question.