php - 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，我想按长度降序排序。但是，它是一个二维数组，我不确定如何实现一个函数来执行我想要的操作。

这是数组的一个例子:

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。所以理想情况下它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"
    )
)

为你能给我的任何帮助干杯。

Answer 1

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

(使用 PHP 5.3 语法)