按列对多维关联数组排序并保留第一级键

Question

我有一个像这样的数组:

$this->wordswithdata = [
    'team1' => [
        'points' => 10,
        'players' => [],
    ],
    'team2' => [
        'points' => 23,
        'players' => []
    ]
];

，我想按照每个球队的得分从高到低对这些球队进行排序。我试过了:

function sort_by_points($a,$b)
{
    if ($a['points'] == $b['points']) return 0;
        return ($a['points'] < $b['points']) ? 1 : -1;
}
usort($this->wordswithdata, "sortbycount");

但是这种方法覆盖了包含teamname的键并返回:

[
    0 => [
        'points' => 23,
        'players' => []
    ],
    1 => [
        'points' => 10,
        'players' => [],
    ]
]

是否有任何方法来排序数组而不丢失teamnames作为数组键?

Answer 1

使用sort函数，它应该保留键=>值关联完整。

(旁注:您可以使用return $a['points'] - $b['points']代替if，或者在php7中使用spacehsip <=>操作符，感谢mbom007用于更新)

Answer 2

您可以使用uasort:

uasort($array, function($a, $b) {
    return $a['points'] - $b['points'];
});

该函数使用用户定义的比较函数对数组进行排序，使数组索引与所关联的数组元素保持相关性。

Answer 3

您可以按其值对关联数组进行排序，如下所示

$age = array("Peter"=>"35", "Ben"=>"37", "Joe"=>"43");
function Ascending($a, $b) {   
    if ($a == $b) {        
        return 0;
    }   
        return ($a < $b) ? -1 : 1; 
}  
function Descending($a, $b) {   
    if ($a == $b) {        
        return 0;
    }   
        return ($a > $b) ? -1 : 1; 
}  

echo "Ascending order" ;
uasort($age,"Ascending");
print_r($age);

echo "</br>Descending order" ;
uasort($age,"Descending");
print_r($age);

Answer 4

为了完整起见，该页应该包括使用array_multisort()的方法—该函数默认情况下将保留非数字键。

代码(演示):

array_multisort(
    array_column($array, 'points'),
    SORT_DESC,
    $array
);

---

也就是说，用宇宙飞船操作符调用uasort()并没有错。注意，$b数据位于三通比较运算符的左侧，$a数据位于右侧，实现降序排序。

代码:演示

uasort(
    $array,
    fn($a, $b) => $b['points'] <=> $a['points']
);

Answer 5

试一下这段代码，希望能成功。

function aasort (&$array, $key) {
    $sorter=array();
    $ret=array();
    reset($array);
    foreach ($array as $ii => $va) {
        $sorter[$ii]=$va[$key];
    }
    asort($sorter);
    foreach ($sorter as $ii => $va) {
        $ret[$ii]=$array[$ii];
    }
    $array=$ret;
}
aasort($your_array,"points");

Answer 6

its working fine i giving example
that array need sort
$sumarray=array [▼
  484 => 54.7875
  486 => 53.5375
  487 => 52.9125
  488 => 52.2875
  493 => 54.7875
]
$original=$sumarray;
 $svalue=array_values($sumarray);
  rsort($svalue);
  $sorted=array();
  foreach ($svalue as $key => $value) {
   $kk=array_search($value,$sumarray);
  $sorted[$kk]=$value;
  unset($sumarray[$kk]);
    }
  print_r($original);
    print_r($svalue);
  print_r($sorted);
             //out put
  array:5 [▼
  484 => 54.7875
  486 => 53.5375
  487 => 52.9125
  488 => 52.2875
  493 => 54.7875
]
array:5 [▼
  0 => 54.7875
  1 => 54.7875
  2 => 53.5375
  3 => 52.9125
  4 => 52.2875
]
array:5 [▼
  484 => 54.7875
  493 => 54.7875
  486 => 53.5375
  487 => 52.9125
  488 => 52.2875
]