[ACCEPTED]-Sort Object in PHP-sorting

Almost verbatim from the manual:

function compare_weights($a, $b) { 
    if($a->weight == $b->weight) {
        return 0;
    } 
    return ($a->weight < $b->weight) ? -1 : 1;
} 

usort($unsortedObjectArray, 'compare_weights');

If you 2 want objects to be able to sort themselves, see 1 example 3 here: http://php.net/usort

For php >= 5.3

function osort(&$array, $prop)
{
    usort($array, function($a, $b) use ($prop) {
        return $a->$prop > $b->$prop ? 1 : -1;
    }); 
}

Note that this uses Anonymous 2 functions / closures. Might find reviewing 1 the php docs on that useful.

You can even build the sorting behavior 2 into the class you're sorting, if you want 1 that level of control

class thingy
{
    public $prop1;
    public $prop2;

    static $sortKey;

    public function __construct( $prop1, $prop2 )
    {
        $this->prop1 = $prop1;
        $this->prop2 = $prop2;
    }

    public static function sorter( $a, $b )
    {
        return strcasecmp( $a->{self::$sortKey}, $b->{self::$sortKey} );
    }

    public static function sortByProp( &$collection, $prop )
    {
        self::$sortKey = $prop;
        usort( $collection, array( __CLASS__, 'sorter' ) );
    }

}

$thingies = array(
        new thingy( 'red', 'blue' )
    ,   new thingy( 'apple', 'orange' )
    ,   new thingy( 'black', 'white' )
    ,   new thingy( 'democrat', 'republican' )
);

print_r( $thingies );

thingy::sortByProp( $thingies, 'prop1' );

print_r( $thingies );

thingy::sortByProp( $thingies, 'prop2' );

print_r( $thingies );

For that compare function, you can just 1 do:

function cmp( $a, $b )
{ 
    return $b->weight - $a->weight;
} 

The usort function (http://uk.php.net/manual/en/function.usort.php) is your friend. Something 2 like...

function objectWeightSort($lhs, $rhs)
{
   if ($lhs->weight == $rhs->weight)
     return 0;

   if ($lhs->weight > $rhs->weight)
     return 1;

   return -1;
}

usort($unsortedObjectArray, "objectWeightSort");

Note that any array keys will be 1 lost.

You could use the usort() function and make your 1 own comparison function.

$sortedObjectArray = usort($unsortedObjectArray, 'sort_by_weight');

function sort_by_weight($a, $b) {
    if ($a->weight == $b->weight) {
        return 0;
    } else if ($a->weight < $b->weight) {
        return -1;
    } else {
        return 1;
    }
}

Update from 2022 - sort array of objects:

usort($array, fn(object $a, object $b): int => $a->weight <=> $b->weight);

Full 1 example:

$array = [
    (object) ['weight' =>  5],
    (object) ['weight' => 10],
    (object) ['weight' =>  1],
];

usort($array, fn(object $a, object $b): int => $a->weight <=> $b->weight);
// Now, $array is sorted by objects' weight.

// display example :
echo json_encode($array);

Output:

[{"weight":1},{"weight":5},{"weight":10}]

Documentation links:

• usort
• spaceship operator (PHP 7.0)
• scalar type declaration (PHP 7.0)
• return type declaration (PHP 7.0)
• arrow function (PHP 7.4)

Depending on the problem you are trying 10 to solve, you may also find the SPL interfaces 9 useful. For example, implementing the ArrayAccess 8 interface would allow you to access your 7 class like an array. Also, implementing 6 the SeekableIterator interface would let 5 you loop through your object just like an 4 array. This way you could sort your object 3 just as if it were a simple array, having 2 full control over the values it returns 1 for a given key.

For more details:

• Zend Article
• PHPriot Article
• PHP Manual

function PHPArrayObjectSorter($array,$sortBy,$direction='asc')
{
    $sortedArray=array();
    $tmpArray=array();
    foreach($this->$array as $obj)
    {
        $tmpArray[]=$obj->$sortBy;
    }
    if($direction=='asc'){
        asort($tmpArray);
    }else{
        arsort($tmpArray);
    }

    foreach($tmpArray as $k=>$tmp){
        $sortedArray[]=$array[$k];
    }

    return $sortedArray;

}

e.g =>

$myAscSortedArrayObject=PHPArrayObjectSorter($unsortedarray,$totalMarks,'asc');

$myDescSortedArrayObject=PHPArrayObjectSorter($unsortedarray,$totalMarks,'desc');

0

You can have almost the same code as you 1 posted with sorted function from Nspl:

use function \nspl\a\sorted;
use function \nspl\op\propertyGetter;
use function \nspl\op\methodCaller;

// Sort by property value
$sortedByWeight = sorted($objects, propertyGetter('weight'));

// Or sort by result of method call
$sortedByWeight = sorted($objects, methodCaller('getWeight'));