如何在多维数组中转置和内爆子数组数据以创建平面输出数组？

Question

我没有指定数量的子数组，但我的数据结构可以如下所示：

array(("john","alex","tyler"),("1","2","3"),("brown","yellow","green"));

上面的例子有 3 个子数组，但问题是这个数字可以改变。

在这个例子中，我需要一个包含 3 个字符串的数组作为最终输出。

array("john,1,brown","alex,2,yellow","tyler,3,green");

我试过用函数来写这个，但找不到解决方案。

Answer 1

使用call_user_func_array、array_map和array_merge函数的解决方案：

$arr = [["john","alex","tyler"],["1","2","3"],["brown","yellow","green"]];

$groups = call_user_func_array("array_map", array_merge([null], $arr));
$result = array_map(function ($v) {
    return implode(",", $v);
}, $groups);

print_r($result);

输出：

Array
(
    [0] => john,1,brown
    [1] => alex,2,yellow
    [2] => tyler,3,green
)

http://php.net/manual/en/function.call-user-func-array.php

Answer 2

在这里，我们通过将数组行转换为列来更改数组的值。然后用逗号（,）内爆每个数组示例：array[1][0] 将变为 array[0][1] 等

PHP code demo

<?php
$array=array(
        array("john","alex","tyler"),
        array("1","2","3"),
        array("brown","yellow","green")
);
$result=array();
for($x=0;$x<count($array);$x++)
{
    for($y=0;$y<count($array[$x]);$y++)
    {
        $result[$x][$y]=$array[$y][$x];//changing array values
    }
}
foreach($result as $key => $value)
{
    $result[$key]=  implode(",", $value);//combining array values on comma(,)
}
print_r($result);

输出：

Array
(
    [0] => john,1,brown
    [1] => alex,2,yellow
    [2] => tyler,3,green
)

Answer 3

更简单的方法使用 argument unpacking (php 5.6+)

<?php

$array = array(array("john","alex","tyler"),array("1","2","3"),array("brown","yellow","green"));

$result = array_map(function(...$elements) { return implode(",", $elements); }, ...$array);

print_r($result);

与其他回复相同的结果。

下面是更详细的内容：

array_map(/* anonymomous function */, ...$array);

...$array 获取嵌套数组并将其解包，就像调用

array_map(/* anonymomous function */, $array[0], $array[1], ... $array[n])

array_map 可能采用多个数组并将给定的可调用对象应用于每一轮。

而匿名函数或多或少做了相反的事情

function(...$elements) { return implode(",", $elements); }

...$elements 接受任意数量的参数并将它们变成一个数组，然后将其连接成一个字符串。

Answer 4

@ultradurable3 这也可以做到 array_column() 在这里你不必担心子阵列的数量，尝试如下：

<?php
$array =  array(array("john","alex","tyler"), array("1","2","3"), array("brown","yellow","green"));
$finalArr = array(implode(",", array_column($array, 0)), implode(",", array_column($array, 1)), implode(",", array_column($array, 2)));
echo "<pre>";
print_r($finalArr);

如何在多维数组中转置和内爆子数组数据以创建平面输出数组？

How to transpose and implode subarray data within a multidimensional array to create a flat output array?

php

arrays

multidimensional-array

transpose

implode