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PHP example code for sorting a two-dimensional array by a specified key value

高洛峰
高洛峰Original
2016-12-22 11:22:532067browse

function array_sort($array, $key){ 
if(is_array($array)){ 
$key_array = null; 
$new_array = null; 
for( $i = 0; $i < count( $array ); $i++ ){ 
$key_array[$array[$i][$key]] = $i; 
} 
ksort($key_array); 
$j = 0; 
foreach($key_array as $k => $v){ 
$new_array[$j] = $array[$v]; 
$j++; 
} 
unset($key_array); 
return $new_array; 
}else{ 
return $array; 
} 
}

PHP two-dimensional array sorting by key value

array_multisort() in PHP can be used to sort multiple arrays at one time, or to sort multi-dimensional arrays according to a certain dimension or multiple dimensions. The associated key names remain unchanged, but the numeric key names are re-indexed. The input arrays are treated as columns of a table and sorted by rows, with the first array being the main array to be sorted. If the rows (values) in the array are compared to be the same, they are sorted according to the size of the corresponding value in the next input array, and so on.

But if the array that needs to be sorted is a two-dimensional array, it needs to be sorted according to the key value of the array. For example, the two-dimensional array below needs to be sorted according to the sort key name, then array_multisort() cannot be implemented directly:

$data[5] = array(&#39;volume&#39; => 67, &#39;edition&#39; => 2);
$data[4] = array(&#39;volume&#39; => 86, &#39;edition&#39; => 1);
$data[2] = array(&#39;volume&#39; => 85, &#39;edition&#39; => 6);
$data[3] = array(&#39;volume&#39; => 98, &#39;edition&#39; => 2);
$data[1] = array(&#39;volume&#39; => 86, &#39;edition&#39; => 6);
$data[6] = array(&#39;volume&#39; => 67, &#39;edition&#39; => 7);
// 准备要排序的数组
foreach ($data as $k => $v) {
  $edition[] = $v[&#39;edition&#39;];
}
array_multisort($edition, SORT_ASC, $data);
print_r($data);

Output:

Array
(
  [0] => Array
    (
      [volume] => 86
      [edition] => 1
    )
 
  [1] => Array
    (
      [volume] => 67
      [edition] => 2
    )
 
  [2] => Array
    (
      [volume] => 98
      [edition] => 2
    )
 
  [3] => Array
    (
      [volume] => 85
      [edition] => 6
    )
 
  [4] => Array
    (
      [volume] => 86
      [edition] => 6
    )
 
  [5] => Array
    (
      [volume] => 67
      [edition] => 7
    )
 
)

In order not to destroy the original key, I wrote a sorting function that only supports two-dimensional arrays.

/**
* 根据数组中的某个键值大小进行排序,仅支持二维数组
* 
* @param array $array 排序数组
* @param string $key 键值
* @param bool $asc 默认正序
* @return array 排序后数组
*/
function arraySortByKey(array $array, $key, $asc = true) 
{
  $result = array();
  // 整理出准备排序的数组
  foreach ( $array as $k => &$v ) {
    $values[$k] = isset($v[$key]) ? $v[$key] : &#39;&#39;;
  }
  unset($v);
  // 对需要排序键值进行排序
  $asc ? asort($values) : arsort($values);
  // 重新排列原有数组
  foreach ( $values as $k => $v ) {
    $result[$k] = $array[$k];
  }
  
  return $result;
}

For more PHP sample code for sorting two-dimensional arrays by specified key values, please pay attention to the PHP Chinese website!

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