Question

我在PHP中有一个多维数组，显示为：

Array
(
    [0] => Array
    (
        [background] => https://example.com/image.jpg
        [description] => Example text
        [url] => https://example.com
    )

    [1] => Array
    (
        [background] => https://example.com/image.jpg
        [description] => Example text
        [url] => https://example.com
    )
)

我想遍历此数组并将相同的参数附加到url个键。我尝试通过带有双foreach循环的函数执行此操作，并且能够成功附加参数，但是我无法返回具有更新值的数组。

这是我尝试过的：

拨打

$array = append_field($array, 'url', '?parameter=test');

功能

function append_field($array, $field, $parameter)
{
    foreach ($array as $inner_array) :
        foreach ($inner_array as $key => $append) :
            if ($key == $field) :
                $append .= $parameter;
            endif;
        endforeach;
    endforeach;

    return $array;
}

Answer 1

您需要在两个foreach循环中将数组值作为引用传递，以便能够写入它们。否则，您将迭代您的值的副本。

参考：http://php.net/manual/en/language.references.php

function append_field($array, $field, $parameter)
{
    foreach ($array as &$inner_array) :
        foreach ($inner_array as $key => &$append) :
            if ($key == $field) :
                $append .= $parameter;
            endif;
        endforeach;
    endforeach;

    return $array;
}

但是你也可以在没有引用的情况下完成它，这次是通过写入包括两个键的完整数组路径：

function append_field($array, $field, $parameter)
{
    foreach ($array as $i => $inner_array) :
        foreach ($inner_array as $key => $append) :
            if ($key == $field) :
                $array[$i][$key] .= $parameter;
            endif;
        endforeach;
    endforeach;

    return $array;
}

Answer 2

只需更改此行

即可

$append .= $parameter;

到这个

$inner_array[$key] = $append.$parameter

和foreach ($array as $inner_array):到foreach ($array as &$inner_array) :

Answer 3

更多方法，以获得相同的结果，例如使用array_map()

[akshay@localhost tmp]$ cat test.php
<?php
$arr = array(
    array(
        'background'=>'https://example.com/image.jpg',
        'description'=>'Example text',
        'url'=>'https://example.com'
    ),
    array(
        'background'=>'https://example.com/image.jpg',
        'description'=>'Example text',
        'url'=>'https://example.com'
    ),

);

$append = array('url'=>'?parameter=test');
print_r( 
    array_map(function($item) use ($append) {foreach($append as $k => $v){ if(isset($item[$k]))$item[$k].=$v;}return $item;}, $arr )
);


?>

输出：

[akshay@localhost tmp]$ php test.php
Array
(
    [0] => Array
        (
            [background] => https://example.com/image.jpg
            [description] => Example text
            [url] => https://example.com?parameter=test
        )

    [1] => Array
        (
            [background] => https://example.com/image.jpg
            [description] => Example text
            [url] => https://example.com?parameter=test
        )

)

将值附加到多维数组PHP

3 个答案: