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

thimoschroeder
thimoschroeder
23,470 Points
Posted by thimoschroeder
thimoschroeder
23,470 Points

Asort clarification needed !

Hey,

it's hard to grasp what's happening when we use the following line of code: 

$sort = $item["title"]; 
$output[$id] = $sort;

Can anybody clarify this for understanding purposes?

Any help is highly appreciated !

Code function:

foreach ($catalog as $id => $item) {
        if (strtolower($category) == strtolower($item["category"])) {
            $sort = $item["title"];
            $output[$id] = $sort;            
        }
    }
    asort($output);
    return array_keys($output);
}
Ashish Mehra
Ashish Mehra
Courses Plus Student 340 Points

Hey thimoschroeder,

I'll try to explain you through comments may it will help you

foreach ($catalog as $id => $item) {    //using foreach we're looping through catalog array 
                                                               //here id is a key i.e [101][201] & item is an value in form of array which contain data
        if (strtolower($category) == strtolower($item["category"])) {  
//if the category(getting through function)  match with item category we execute below code
            $sort = $item["title"];  //here we create new variable with name sort and assign it value of current [item] title  
            $output[$id] = $sort;            //here we're pussing the $sort variable along with key i.e. catalog[key]  
        }
    }
    asort($output);  //here we're sorting the $output on the basis of title 
    return array_keys($output); //now here we're returning all the keys i.e.[101],[102] in the sorted order
}

hope it help you

1 Answer

thimoschroeder
thimoschroeder
23,470 Points
thimoschroeder
thimoschroeder
23,470 Points

@ Ashish mehra - Thanks for your efforts, I got clear now, however I'm still struggling to understand when to use this:

$output[$id] = $sort;

Ashish Mehra
Ashish Mehra
Courses Plus Student 340 Points

We'have data like this in data.php file

 $catalog[101] = [
        "title" => "A Design Patterns: Elements of Reusable Object-Oriented Software",
        "img" => "img/media/design_patterns.jpg",
        "genre" => "Tech",
        "format" => "Paperback",
        "year" => 1994,
        "category" => "Books",
        "authors" => [
            "Erich Gamma",
            "Richard Helm",
            "Ralph Johnson",
            "John Vlissides"
        ],
        "publisher" => "Prentice Hall",
        "isbn" => '978-0201633610'
    ];
    $catalog[102] = [
        "title" => "Clean Code: A Handbook of Agile Software Craftsmanship",
        "img" => "img/media/clean_code.jpg",
        "genre" => "Tech",
        "format" => "Ebook",
        "year" => 2008,
        "category" => "Books",
        "authors" => [
            "Robert C. Martin"
        ],
        "publisher" => "Prentice Hall",
        "isbn" => '978-0132350884'
    ];

In function.php we've some code like this

 function catalog_sel($catalog,$category){

      $output = [];

      foreach ($catalog as $key => $value) {
         if($category==null OR strtolower($category)==strtolower($value["category"])){
            $sort = $value["title"];
            $output[$key] = $sort;
         }
      }
     asort($output);
     return array_keys($output);
   }

now here in function.php we create an empty array $output and below in statement we define $output[$key] = $sort; which assigned data to an empty array like this $output[102] = "Clean Code: A Handbook of Agile Software Craftsmanship" , $output[101] = "A Design Patterns: Elements of Reusable Object-Oriented Software" (in sorted order) but we don't want to return title to our function back we want to return the keys of function that's why we create an $output as an associative array so that we can hold the keys of particular title in the order that sorted.