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PHP

Posted by Aayush Masiwal
Aayush Masiwal
Courses Plus Student 895 Points

isset($catalog[id]);

<?php
  //inlcuding data
  include("include/data.php");
  include("include/functions.php");

if(isset($_GET["id"])){

    $id = $_GET["id"];  
    if(isset($catalog[$id])){  //what's the purpose of using isset here
        $item = $catalog[$id];
    }
 }
 if(!isset($item)){
    header("location:catalog.php");
    exit;
 }
  $p_title = $item["title"];
  $sections = null;

 include("include/header.php");

?>

1 Answer

jcorum
jcorum
71,828 Points

Here's what the PHP manual (http://php.net/manual/en/function.isset.php) has to say:

Determine if a variable is set and is not NULL

By "is set" it means "has a value".

Aayush Masiwal
Aayush Masiwal
Courses Plus Student 895 Points

Thanks