在PHP中操作多维数组

Question

我手头有以下数组.我必须迭代以下数组,以便它将在新数组的第0个索引上创建另一个数组,其输出为每个子数组的第0个索引,依此类推.

当前阵列

 Array
    (
        [0] => Array
            (
                [0] => 1
                [1] => 2
                [2] => 3
            )

        [1] => Array
            (
                [0] => 1
                [1] => 2
                [2] => 3
            )

        [2] => Array
            (
                [0] => 1
                [1] => 2
                [2] => 3
            )

    )

期望的输出

Array
    (
        [0] => Array
            (
                [0] => 1
                [1] => 1
                [2] => 1
            )

        [1] => Array
            (
                [0] => 2
                [1] => 2
                [2] => 2
            )

        [2] => Array
            (
                [0] => 3
                [1] => 3
                [2] => 3
            )

    )

Answer 1

对于PHP版本> = 5.5.0,您有array_column()函数:

$newArray = array_column(
    $oldArray,
    0
);

对于早期版本的PHP,您可以使用array_map()

$column = 0;
$newArray = array_map(
    function ($value) use ($column) {
        return $value[$column];
    },
    $oldArray
);