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 = $val\n"; } ?>
以上例程会输出:
d = lemon c = apple b = banana a = orange
参见
Best deal sorting: This is a function that will sort an array with integer keys (weight) and float values (cost) and delete 'bad deals' - entries that are more costly than other entries that have greater or equal weight. Input: an array of unsorted weight/cost pairs Output: none function BEST_DEALS($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; } ?>