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PHP Build a Basic PHP Website (2018) Listing and Sorting Inventory Items Sorting Array Items

Obayanju Damilare
Obayanju Damilare
3,383 Points
Posted by Obayanju Damilare
Obayanju Damilare
3,383 Points

Why does $output change to a string

I changed this line of code :

$output[$id] = $sort;

to

$output = $sort;

and I used 

$output

in the asort function instead of 

$output[$id]

and then php tells me that asort parameter which is 

 $output

is a string. But we have already defined 

$output = array();

at the beginning of the array_category function, why then does php recognize it as a string when I use it in asort. Thanks for your answer in advance :)

1 Answer

Jennifer Nordell
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STAFF
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Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there! The reason it changes from an array to a string is because the variable is now being entirely redefined and overwritten with a string. When you do $output = $sort; you are telling PHP to take the entirety of the array and replace it with that string that's contained in the $sort variable.

I made a little code snippet that I encourage you to run in workspaces which will show what's happening a little more clearly.

<?php
$testArr = array();
var_dump($testArr); // testArr is now an array

$testArr = "Hi there!";
var_dump($testArr);  //testArr is now a string

$testArr = array();  
var_dump($testArr);  //testArr is now an array

$testArr = 2.39093;
var_dump($testArr);  //testArr is now a float

?>

We start with an array. Then we replace the entirety of the array with a string. This is perfectly valid PHP, but probably not what we're intending. We probably wanted to replace an element inside the array with a string... not the entire array. So then we redeclare it as an empty array. This time we replace the entire array with a float. Once again, this is perfectly valid, but likely not what we're intending.

Hope this helps! :sparkles: