PHP Notice: Undefined index although using try\catch

Question

This is my try/catch block in PHP:

try {     $api = new api($_GET["id"]);     echo $api -> processRequest(); } catch (Exception $e) {     $error = array("error" => $e->getMessage());     echo json_encode($error); } 

When there is nothing in the $_GET["id"], I still get the notice error. How can I avoid getting this error?

Answer 1

use isset function to check if the variable is set or not:

if( isset($_GET['id'])){     $api = new api($_GET["id"]);     echo $api -> processRequest(); } 

Answer 2

If you want a fast and "dirty" solution, you can use

$api = new api(@$_GET["id"]); 

Edit:

Since PHP 7.0 there is a much better and accepted solution: using the null coalescing operator (??). With it you can shorten your code to

$api = new api($_GET["id"] ?? null); 

and you don't get a notice because you defined what should happen in the case the variable is not defined.