PHP 警告 : array_filter() expects parameter 2 to be a valid callback, 第二个数组成员不是有效方法

Question

我最初有这个大数组，它是从我的数据库中以缩短的形式获得的:

$arreglo =Array
(
    "0" => Array
        (
            "concurso" => 2600,
            "R1" => 1
        ),

    "1" => Array
        (
            "concurso" => 2602,
            "R1" => 1
        ),

    "2" => Array
        (
            "concurso" => 2603,
            "R1" => 1
        ),

    "3" => Array
        (
            "concurso" => 2648,
            "R1" => 1
        ),

    "4" => Array
        (
            "concurso" => 2653,
            "R1" => 1
        ),

    "5" => Array
        (
            "concurso" => 2655,
            "R1" => 1
        ),

    "6" => Array
        (
            "concurso" => 2698,
            "R1" => 1
        ),

    "7" => Array
        (
            "concurso" => 2722,
            "R1" => 1
        ),

    "8" => Array
        (
            "concurso" => 2741,
            "R1" => 1
        ),

    "9" => Array
        (
            "concurso" => 2743,
            "R1" => 1
        ),

    "10" => Array
        (
            "concurso" => 2744,
            "R1" => 1
        ),

    "11" => Array
        (
            "concurso" => 2745,
            "R1" => 1
        ),

    "12" => Array
        (
            "concurso" => 2763,
            "R1" => 1
        ),

    "13" => Array
        (
            "concurso" => 2778,
            "R1" => 1
        ),

    "14" => Array
        (
            "concurso" => 2780,
            "R1" => 1
        ),

    "15" => Array
        (
            "concurso" => 2782,
            "R1" => 1
        ),

    "16" => Array
        (
            "concurso" => 2607,
            "R1" => 2
        ),

    "17" => Array
        (
            "concurso" => 2609,
            "R1" => 2
        )
);

一直持续到“R1”元素值为 56。

所以我想分开 R1 的每组值，例如，当 R1 等于 1 时，我使用以下函数将“concurso”的每个值存储在一个名为“$concursos”的数组中:

function category($var)
{
    return (is_array($var) && $var['R1'] == 1);
}
$current=array_filter($arreglo,"category");

到现在为止一切正常，因为当 R1 = 1 时，我只得到当 R1 = 1 时的 concursos 列表，如下所示:

Array
(
    [0] => 2600
    [1] => 2602
    [2] => 2603
    [3] => 2648
    [4] => 2653
    [5] => 2655
    [6] => 2698
    [7] => 2722
    [8] => 2741
    [9] => 2743
    [10] => 2744
    [11] => 2745
    [12] => 2763
    [13] => 2778
    [14] => 2780
    [15] => 2782
)

问题是，如果我想在 for 循环中对 R1=2,3,...56 的以下数字再次进行此操作，那么，我将设置 ==$ 而不是指定 ==1 currentR1，在函数中是这样的:

function category($var)
    {
        return (is_array($var) && $var['R1'] == $currentR1);
    }
    $current=array_filter($arreglo,"category");

现在的问题是，如果我尝试输入参数，函数调用失败，我如何在这里指定一个参数？

我试过，例如，

$current=array_filter($repeticiones,array('category',$l));

它没有警告我

警告:array_filter() 期望参数 2 是有效的回调，第二个数组成员不是第 X 行 myScript.php 中的有效方法

那我该如何指定参数呢？

Answer 1

你可以像这样使用匿名函数:

$r = 2;
$current = array_filter($arreglo, function($var) use ($r){
                                                 // ^ import variable to the closure scope
    return (is_array($var) && $var['R1'] == $r);
});