krsort()

(PHP 4, PHP 5, PHP 7)

对数组按照键名逆向排序

说明

krsort(array &$array[,int $sort_flags= SORT_REGULAR] ): bool

对数组按照键名逆向排序，保留键名到数据的关联。主要用于结合数组。

参数

$array

输入的数组。

$sort_flags

可以用可选参数$sort_flags改变排序的行为，详情见 sort()。

返回值

成功时返回TRUE，或者在失败时返回FALSE。

范例

Example #1krsort()例子

<?php
$fruits = array("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple");
krsort($fruits);
foreach ($fruits as $key => $val) {
    echo "$key = $val\n";
}
?>

以上例程会输出：

d = lemon
c = apple
b = banana
a = orange

参见

• arsort()对数组进行逆向排序并保持索引关系
• ksort()对数组按照键名排序
• 数组排序函数对比

Best deal sorting:
This is a function that will sort an array with integer keys (weight) and float values (cost) and delete 'bad deals' - entries that are more costly than other entries that have greater or equal weight.
Input: an array of unsorted weight/cost pairs
Output: none
function BEST_DEALS($myarray)
{  // most weight for least cost:
  //  Peter Kionga-Kamau, http://www.pmkmedia.com
  // thanks to Nafeh for the reversal trick
  // free for unrestricted use.
  krsort($myarray, SORT_NUMERIC);
  while(list($weight, $cost) = each($myarray))
  {  // delete bad deals, retain best deals:
    if(!$lastweight)
    {
      $lastweight=$weight;
      $lastcost = $cost;
    }
    else if($cost >= $lastcost) unset($myarray[$weight]);
    else
    {
      $lastweight=$weight;
      $lastcost = $cost;
    }
  }
  ksort($myarray);
}

To create a natural reverse sorting by keys, use the following function:
<?php
function natkrsort($array) 
{
  $keys = array_keys($array);
  natsort($keys);
  foreach ($keys as $k)
  {
    $new_array[$k] = $array[$k];
  }
  
  $new_array = array_reverse($new_array, true);
  return $new_array;
}
?>