PHP检查不同数组中的某些值是否对所有人都相同

Question

我有几个这样的数组

$arrayOne = array (
    "name" => 'john',
    "position" => 'instructor',
    "hired"  => '2010',
    "department" => 'math',
);

$arrayTwo = array (
    "name" => 'smith',
    "position" => 'instructor',
    "hired"  => '2010',
    "department" => 'math',
);  

$arrayThree = array (
    "name" => 'dave',
    "position" => 'instructor',
    "hired"  => '2009',
    "department" => 'math',
);  

如何检查这些阵列是否都具有相同的雇用日期？

一种方法是比较每个人：

if($arrayOne['hired'] === $arrayTwo['hired']) & if($arrayOne['hired'] === $arrayThree['hired']) & ...

但是有没有更干净的方法来做到这一点？

Answer 1

你最初的问题和随后的评论是相似的，但他们试图用数据做不同的事情，结果不同。 最初被问到的是：

我如何检查这些数组是否都具有相同的雇用日期

这可以通过以下方式完成：

var_dump(count(array_unique(array_column([$arrayOne, $arrayTwo, $arrayThree], 'hired'))));

// or

$combined = [$arrayOne, $arrayTwo, $arrayThree];
$hiredValues = array_column($combined, 'hired');
$hiredValuesUnique = array_unique($hiredValues);
$length = count($hiredValuesUnique);
var_dump($length);

如果count为1 ，则它们相同，否则它们不同。

但是，您的后续评论是

我怎么知道哪些是相同的

为此，我将创建一个由该值键控的新数组，并在源数组上foreach ，有效地将相似的数组分组以便您进一步操作。

$final = [];

foreach([$arrayOne, $arrayTwo, $arrayThree] as $array){
    if(!array_key_exists($array['hired'], $final)){
        $final[$array['hired']] = [];
    }
    $final[$array['hired']][] = $array;
}

var_dump($final);

其中产生：

array(2) {
  [2010]=>
  array(2) {
    [0]=>
    array(4) {
      ["name"]=>
      string(4) "john"
      ["position"]=>
      string(10) "instructor"
      ["hired"]=>
      string(4) "2010"
      ["department"]=>
      string(4) "math"
    }
    [1]=>
    array(4) {
      ["name"]=>
      string(5) "smith"
      ["position"]=>
      string(10) "instructor"
      ["hired"]=>
      string(4) "2010"
      ["department"]=>
      string(4) "math"
    }
  }
  [2009]=>
  array(1) {
    [0]=>
    array(4) {
      ["name"]=>
      string(4) "dave"
      ["position"]=>
      string(10) "instructor"
      ["hired"]=>
      string(4) "2009"
      ["department"]=>
      string(4) "math"
    }
  }
}

Answer 2

我写了下面的代码：

//Your data
$arrayOne = array (
    "name" => 'john',
    "position" => 'instructor',
    "hired"  => '2010',
    "department" => 'math',
);

$arrayTwo = array (
    "name" => 'smith',
    "position" => 'instructor',
    "hired"  => '2010',
    "department" => 'math',
);  

$arrayThree = array (
    "name" => 'dave',
    "position" => 'instructor',
    "hired"  => '2009',
    "department" => 'math',
);  

function hiredIsTheSameEverywhere(...$arrays) : bool  
{
    return count(array_count_values(array_column($arrays, "hired"))) === 1; 
}

function whereHiredIsTheSame(...$arrays) : array 
{
    $return = [];
    $count = array_count_values(array_column($arrays, "hired"));
    foreach($arrays as $array) {
        if($count[$array['hired']] > 1) {
            $return[$array['hired']][] = $array;
        }
    }
    return $return;
}

//The output 
var_dump(hiredIsTheSameEverywhere($arrayOne, $arrayTwo, $arrayThree));
var_dump(whereHiredIsTheSame($arrayOne, $arrayTwo, $arrayThree));

输出：

bool(false)
array(1) {
  [2010]=>
  array(2) {
    [0]=>
    array(4) {
      ["name"]=>
      string(4) "john"
      ["position"]=>
      string(10) "instructor"
      ["hired"]=>
      string(4) "2010"
      ["department"]=>
      string(4) "math"
    }
    [1]=>
    array(4) {
      ["name"]=>
      string(5) "smith"
      ["position"]=>
      string(10) "instructor"
      ["hired"]=>
      string(4) "2010"
      ["department"]=>
      string(4) "math"
    }
  }
}