Sort array of objects by object fields

Question

How can I sort this array of objects by one of its fields, like name or count ?

  Array
(
    [0] => stdClass Object
        (
          


        

Answer 1

Heres a nicer way using closures

usort($your_data, function($a, $b)
{
    return strcmp($a->name, $b->name);
});

Please note this is not in PHP's documentation but if you using 5.3+ closures are supported where callable arguments can be provided.

Answer 2

Use usort, here's an example adapted from the manual:

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

usort($your_data, "cmp");

You can also use any callable as the second argument. Here are some examples:

• Using anonymous functions (from PHP 5.3)

    usort($your_data, function($a, $b) {return strcmp($a->name, $b->name);});
  

• From inside a class

    usort($your_data, array($this, "cmp")); // "cmp" should be a method in the class
  

• Using arrow functions (from PHP 7.4)

    usort($your_data, fn($a, $b) => strcmp($a->name, $b->name));
  

Also, if you're comparing numeric values, fn($a, $b) => $a->count - $b->count as the "compare" function should do the trick, or, if you want yet another way of doing the same thing, starting from PHP 7 you can use the Spaceship operator, like this: fn($a, $b) => $a->count <=> $b->count.

Answer 3

You can use this function (works in PHP Version >= 5.3):

function sortArrayByKey(&$array,$key,$string = false,$asc = true){
    if($string){
        usort($array,function ($a, $b) use(&$key,&$asc)
        {
            if($asc)    return strcmp(strtolower($a{$key}), strtolower($b{$key}));
            else        return strcmp(strtolower($b{$key}), strtolower($a{$key}));
        });
    }else{
        usort($array,function ($a, $b) use(&$key,&$asc)
        {
            if($a[$key] == $b{$key}){return 0;}
            if($asc) return ($a{$key} < $b{$key}) ? -1 : 1;
            else     return ($a{$key} > $b{$key}) ? -1 : 1;

        });
    }
}

Example:

sortArrayByKey($yourArray,"name",true); //String sort (ascending order)
sortArrayByKey($yourArray,"name",true,false); //String sort (descending order)
sortArrayByKey($yourArray,"id"); //number sort (ascending order)
sortArrayByKey($yourArray,"count",false,false); //number sort (descending order)

Answer 4

reference answer of Demodave to eating multi key

 function array_sort_by(array $arr, $keys){

    if(!is_array($keys))
        $keyList = explode(',', $keys);
    $keyList = array_keys(array_flip($keyList)); // array_unique 
    $keyList = array_reverse($keyList);

    $result = &$arr;
    foreach ($keyList as $key) {
        if(array_key_exists($key, $arr))
            $result = usort($result, function($a, $b) use ($key) { return strcmp($a->{$key}, $b->{$key}); });
    }
    return $result;
}

Answer 5

if you want to sort dates

   usort($threads,function($first,$second){
        return strtotime($first->dateandtime) < strtotime($second->dateandtime);
    });

Answer 6

If you want to sort integer values:

// Desc sort
usort($array,function($first,$second){
    return $first->number < $second->number;
});

// Asc sort
usort($array,function($first,$second){
    return $first->number > $second->number;
});

UPDATED with the string don't forget to convert to the same register (upper or lower)

// Desc sort
usort($array,function($first,$second){
    return strtolower($first->text) < strtolower($second->text);
});

// Asc sort
usort($array,function($first,$second){
    return strtolower($first->text) > strtolower($second->text);
});