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PHP Build a Basic PHP Website (2018) Listing and Sorting Inventory Items Displaying Item Details

where did the data "id" come from that's stored in the variable $id and the variable $item?

it isn't very clear to me why suddenly we have data "id"? from what i understood, we can only get a data that's exist in our array? therefore, this line of code confused me :

$id = $_GET["id"]; if (isset($catalog[$id])) { $item = $catalog[$id]; }

1 Answer

Steven Parker
Steven Parker
231,072 Points

The $_GET array is an associative array of variables that were passed to the current script via the URL parameters (the "query string"). This code takes the value that was passed in with the name "id" and puts it into the $id variable.

Then that value is used as the index into the $catalog array.