如何基于嵌套数组的value列过滤PHP多维数组？

给定如下PHP多维数组：

$array = [    
    0 => [  
        "label"    =>  "Radiator",  
        "details"  => [  
            0 => [  
                "label"     => "Condition",  
                "value"     => "New",
            ], 
            1 => [  
                "label"     => "Type",  
                "value"     => "Wall",
            ],
        ],
    ],  
    1 => [  
        "label"    =>  "Airco",  
        "details"  => [  
            0 => [  
                "label"     => "Condition",  
                "value"     => "New",
            ], 
            1 => [  
                "label"     => "Type",  
                "value"     => "",
            ], 
        ],
    ], 
    2 => [  
        "label"    =>  "Refrigerator",  
        "details"  => [  
            0 => [  
                "label"     => "Condition",  
                "value"     => "Bad",
            ], 
            1 => [  
                "label"     => "Type",  
                "value"     => "Wall",
            ], 
        ],
    ], 
];

需要过滤掉details中value为空（含空白字符）的子项，最终得到如下结果：

$array = [    
    0 => [  
        "label"    =>  "Radiator",  
        "details"  => [  
            0 => [  
                "label"     => "Condition",  
                "value"     => "New",
            ], 
            1 => [  
                "label"     => "Type",  
                "value"     => "Wall",
            ],
        ],
    ],  
    1 => [  
        "label"    =>  "Airco",  
        "details"  => [  
            0 => [  
                "label"     => "Condition",  
                "value"     => "New",
            ],
        ],
    ], 
    2 => [  
        "label"    =>  "Refrigerator",  
        "details"  => [  
            0 => [  
                "label"     => "Condition",  
                "value"     => "Bad",
            ], 
            1 => [  
                "label"     => "Type",  
                "value"     => "Wall",
            ], 
        ],
    ], 
];

你之前了解的单层数组过滤逻辑需要调整，因为这里存在嵌套结构。可以通过遍历外层数组，对每个元素的details子数组单独应用过滤逻辑来实现：

// 遍历外层数组，处理每个设备项
$result = array_map(function($item) {
    // 过滤details数组，保留value非空的子项
    $item['details'] = array_filter($item['details'], function($detail) {
        return trim($detail['value']) !== '' && $detail['value'] !== null;
    });
    return $item;
}, $array);

// 可选：重置details的索引为连续数字，避免过滤后出现断号
foreach ($result as &$item) {
    $item['details'] = array_values($item['details']);
}
unset($item); // 释放引用

代码说明 #

1. 用array_map遍历外层数组的每个设备项，确保原有的label等字段完整保留
2. 对每个设备的details数组，用array_filter筛选出value经过trim后不为空字符串且不为null的子项
3. 最后的array_values操作是可选的，用来把过滤后的details数组重置为连续数字索引，避免出现断号的情况

内容的提问来源于stack exchange，提问作者Senne Vandenputte