Question

我需要删除数组中的重复项，但它们并不完全重复（所以我不能使用array_unique）。实际上我需要忽略'重复检查'中的一个字段。在下面的示例中，我希望在检查中忽略“RecipientEmail”，因此我应删除第三个元素：

Array
(
    [0] => Array
        (
            [RecipientID] => 1
            [RecipientScreenname] => Lau T
            [RecipientFirstname] => TK
            [RecipientEmail] => lau@xx.co.uk
        )

    [1] => Array
        (
            [RecipientID] => 3
            [RecipientScreenname] => Tom L
            [RecipientFirstname] => Thomas
            [RecipientEmail] => info@xx.com
        )        

    [2] => Array
        (
            [RecipientID] => 1
            [RecipientScreenname] => Lau T
            [RecipientFirstname] => TK
            [RecipientEmail] => other@xx.co.uk
        )        

)

有没有办法使用任何本机PHP函数？

Answer 1

一行解决方案没有循环：

array_filter($list, function($el) use(&$unique) { return isset($unique[$key = "{$el['RecipientID']}-{$el['RecipientScreenname']}-{$el['RecipientFirstname']}"]) ? 0 : ($unique[$key] = 1); });

相同但格式化：

array_filter(
            $list,
            function ($el) use (&$unique) {
                return isset($unique[$key = "{$el['RecipientID']}-{$el['RecipientScreenname']}-{$el['RecipientFirstname']}"]) ? 0 : ($unique[$key] = 1);
            }
        );

Answer 2

只需在RecipientID上重新编制索引即可获得一个。如果你需要第一个使用它，如果你需要最后一个，那么使用array_reverse($array)：

$result = array_column($array, null, 'RecipientID');

如果RecipientID不能用于唯一性，那么您可以使用值构建密钥。再次，使用此或array_reverse($array)：

foreach($array as $v) {
    $result[$v['RecipientID'].'-'
           .$v['RecipientScreenname'].'-'
           .$v['RecipientFirstname']
           ] = $v;
}

如果需要，请$result = array_values($result)。

Answer 3

我为你写了一个函数。看看是否有效：

function make_unique($input, $ignore_column)
{ 
    $input = array_reverse($input);
    $orig = $input; 
    array_walk($input, function (&$v) use ($ignore_column) {
            unset($v[$ignore_column]);
        });

    foreach($orig as $index =>$val)
    {
        unset($input[$index]);
        unset($val[$ignore_column]);
        if(in_array($val, $input))
            unset($orig[$index]); 
    } 

    return(array_reverse($orig));
}
var_dump($input);
var_dump(make_unique($input, 'RecipientEmail'));

尝试使用以下输入：

$input =[
   [
        'RecipientID' => '1',
        'RecipientScreenname' => 'Lau T',
        'RecipientFirstname' => 'TK',
        'RecipientEmail' => 'lau@xx.co.uk'
    ],
    [
        'RecipientID' => '2',
        'RecipientScreenname' => 'Tom hanks L',
        'RecipientFirstname' => 'Thomas',
        'RecipientEmail' => 'info@xx.com',
   ],
    [
        'RecipientID' => '3',
        'RecipientScreenname' => 'Tom L',
        'RecipientFirstname' => 'Thomas',
        'RecipientEmail' => 'info@xx.com',
   ],
    [
        'RecipientID' => '4',
        'RecipientScreenname' => '444',
        'RecipientFirstname' => 'Thomas',
        'RecipientEmail' => 'info@xx.com',
   ],
    [
        'RecipientID' => '2',
        'RecipientScreenname' => 'Tom hanks L',
        'RecipientFirstname' => 'Thomas',
        'RecipientEmail' => 'infsdfsdfo@xx.com',
   ],
   [
        'RecipientID' => '1',
        'RecipientScreenname' => 'Lau T',
        'RecipientFirstname' => 'TK',
        'RecipientEmail' => 'other@xx.co.uk',
    ]  
];

删除数组中的重复项，而不使用array_unique

3 个答案: