array_multisort()：数组大小不一致

Question

我正在尝试使用array_multisort()函数根据数组的子数组对数组进行排序......

在尝试的时候；

print_r($mar); echo '<br>';
$arr2 = array_multisort($mar, array('wek'=>SORT_ASC));
print_r($arr2);

获取错误array_multisort(): Array sizes are inconsistent

排序前的输出为

Array ( 
    [0] => Array ( [dat] => 1 [wek] => 5 [mac] => A100 [mcr] => #00c8ff ) 
    [1] => Array ( [dat] => 2 [wek] => 9 [mac] => A100 [mcr] => #00c8ff ) 
    [2] => Array ( [dat] => 5 [wek] => 13 [mac] => A100 [mcr] => #00c8ff ) 
    [3] => Array ( [dat] => 5 [wek] => 6 [mac] => A101 [mcr] => #ff8800 ) 
    [4] => Array ( [dat] => 13 [wek] => 17 [mac] => A100 [mcr] => #00c8ff ) 
    [5] => Array ( [dat] => 20 [wek] => 21 [mac] => A100 [mcr] => #00c8ff ) 
    [6] => Array ( [dat] => 8 [wek] => 14 [mac] => A101 [mcr] => #ff8800 ) 
)

我需要的是：

Array ( 
    [0] => Array ( [dat] => 1 [wek] => 5 [mac] => A100 [mcr] => #00c8ff ) 
    [3] => Array ( [dat] => 5 [wek] => 6 [mac] => A101 [mcr] => #ff8800 ) 
    [1] => Array ( [dat] => 2 [wek] => 9 [mac] => A100 [mcr] => #00c8ff ) 
    [2] => Array ( [dat] => 5 [wek] => 13 [mac] => A100 [mcr] => #00c8ff ) 
    [6] => Array ( [dat] => 8 [wek] => 14 [mac] => A101 [mcr] => #ff8800 ) 
    [4] => Array ( [dat] => 13 [wek] => 17 [mac] => A100 [mcr] => #00c8ff ) 
    [5] => Array ( [dat] => 20 [wek] => 21 [mac] => A100 [mcr] => #00c8ff ) 
)

Answer 1

以下行存在错误：

$arr2 = array_multisort($mar, array('wek'=>SORT_ASC));

您正在尝试将返回结果存储到数组中，但array_multisort返回的是布尔值，而不是排序后的数组：

执行此操作可对$mar的多维数组进行排序

foreach ($mar as $key => $row)
{
    $wek[$key]  = $row['wek'];
}    

// Sort the data with wek ascending order, add $mar as the last parameter, to sort by the common key

array_multisort($wek, SORT_ASC, $mar);

完成上述操作后，现在可以对$mar数组进行排序。

Answer 2

为了能够使用array_multisort，您应该重新组织数组。请参阅示例#3：http://uk1.php.net/array_multisort

或者您可以使用usort，但它将对密钥进行重新编号：

<?php
$mar =Array (.
    0 => Array ( 'dat' => 1, 'wek' => 5, 'mac' => 'A100', 'mcr' => '#00c8ff' ) ,
    1 => Array ( 'dat' => 2, 'wek' => 9, 'mac' => 'A100', 'mcr' => '#00c8ff' ) ,
    2 => Array ( 'dat' => 5, 'wek' => 13, 'mac' => 'A100', 'mcr' => '#00c8ff' ) ,
    3 => Array ( 'dat' => 5, 'wek' => 6, 'mac' => 'A101', 'mcr' => '#ff8800' ) ,
    4 => Array ( 'dat' => 13, 'wek' => 17, 'mac' => 'A100', 'mcr' => '#00c8ff' ),
    5 => Array ( 'dat' => 20, 'wek' => 21, 'mac' => 'A100', 'mcr' => '#00c8ff' ) ,
    6 => Array ( 'dat' => 8, 'wek' => 14, 'mac' => 'A101', 'mcr' => '#ff8800' ) ,
);

usort($mar, function($a,$b){return $a['wek']-$b['wek'];});
print_r($mar);