如何在PHP中按长度对二维数组进行排序？

Question

我有一个字符串数组,我想按照下降的长度排序.但是,它是一个二维数组,我不知道如何实现一个能满足我想要的功能.

这是一个数组的例子:

Array
(
  [0] => Array
    (
      [0] => "abc"
      [1] => "def"
      [2] => "1234"
    )

  [1] => Array
    (
      [0] => "ghijkl"
      [1] => "092"
      [2] => "234234"
    )

  [2] => Array
    (
      [0] => "mn"
      [1] => "opq"
      [2] => "67843"
    )
)

我只对子数组中第一项的长度感兴趣.理想情况下,最终会看起来像这样:

Array
(
  [0] => Array
    (
      [0] => "ghijkl"
      [1] => "092"
      [2] => "234234"
    )
  [1] => Array
    (
      [0] => "abc"
      [1] => "def"
      [2] => "1234"
    )
  [2] => Array
    (
      [0] => "mn"
      [1] => "opq"
      [2] => "67843"
    )
)

欢呼,你可以给我任何帮助.

Answer 1

usort($array, function ($a, $b) { return strlen($b[0]) - strlen($a[0]); });

(使用PHP 5.3语法)