比较 PHP 中的多维数组

Question

如何比较 php 中的多维数组？有没有简单的方法？

Answer 1

我知道的最简单的方法：

$a == $b;

请注意，您也可以使用===。它们之间的区别是：

1. 对于双等号 ==，顺序很重要：

   $a = array(0 => 'a', 1 => 'b');
   $b = array(1 => 'b', 0 => 'a');
   var_dump($a == $b);  // true
   var_dump($a === $b); // false
   

2. 使用 三等号 ===，类型很重要：

   $a = array(0, 1);
   $b = array('0', '1');
   var_dump($a == $b);  // true
   var_dump($a === $b); // false
   

参考：Array operators

Answer 2

要比较数组的结构，你应该使用恒等运算符。

if($arrayA === $arrayB) {
    ...
}

Answer 3

function multi_diff($arr1,$arr2){
  $result = array();
  foreach ($arr1 as $k=>$v){
    if(!isset($arr2[$k])){
      $result[$k] = $v;
    } else {
      if(is_array($v) && is_array($arr2[$k])){
        $diff = multi_diff($v, $arr2[$k]);
        if(!empty($diff))
          $result[$k] = $diff;
      }
    }
  }
  return $result;
}

//example:

var_dump(multi_diff(

array(
  "A"=>array(
    "A1"=>array('A1-0','A1-1','A1-2','A1-3'),
    "A2"=>array('A2-0','A2-1','A2-2','A2-3'),
    "A3"=>array('A3-0','A3-1','A3-2','A3-3')
  ),
  "B"=>array(
    "B1"=>array('B1-0','B1-1','B1-2','B1-3'),
    "B2"=>array('B2-0','B2-1','B2-2','B2-3'),
    "B3"=>array('B3-0','B3-1','B3-2','B3-3')
  ),
  "C"=>array(
    "C1"=>array('C1-0','C1-1','C1-2','C1-3'),
    "C2"=>array('C2-0','C2-1','C2-2','C2-3'),
    "C3"=>array('C3-0','C3-1','C3-2','C3-3')
  ),
  "D"=>array(
    "D1"=>array('D1-0','D1-1','D1-2','D1-3'),
    "D2"=>array('D2-0','D2-1','D2-2','D2-3'),
    "D3"=>array('D3-0','D3-1','D3-2','D3-3')
  )
),

array(
  "A"=>array(
    "A1"=>array('A1-0','A1-1','A1-2','A1-3'),
    "A2"=>array('A2-0','A2-1','A2-2','A2-3'),
    "A3"=>array('A3-0','A3-1','A3-2')
  ),
  "B"=>array(
    "B1"=>array('B1-0','B1-2','B1-3'),
    "B2"=>array('B2-0','B2-1','B2-2','B2-3'),
    "B3"=>array('B3-0','B3-1','B3-3')
  ),
  "C"=>array(
    "C1"=>array('C1-0','C1-1','C1-2','C1-3'),
    "C3"=>array('C3-0','C3-1')
  ),
  "D"=>array(
    "D1"=>array('D1-0','D1-1','D1-2','D1-3'),
    "D2"=>array('D2-0','D2-1','D2-2','D2-3'),
    "D3"=>array('D3-0','D3-1','D3-2','D3-3')
  )
)

));

Answer 4

另一种方法是serialize() 两个数组并比较字符串。

http://php.net/manual/en/function.serialize.php

Answer 5

$difference = array();
foreach($array1 as $key => $value)
{
    if(is_array($value))
    {
        if(!isset($array2[$key]))
        {
            $difference[$key] = $value;
        }
        elseif(!is_array($array2[$key]))
        {
            $difference[$key] = $value;
        }
        else
        {
            $new_diff = array_diff($value, $array2[$key]);
            if($new_diff != FALSE)
            {
                $difference[$key] = $new_diff;
            }
        }
    }
    elseif(!isset($array2[$key]) || $array2[$key] != $value)
    {
        $difference[$key] = $value;
    }
}

Answer 6

此功能将为您完成所有工作。

您可以使用它来真正比较任何2个相同或完全不同结构的数组。

它会返回：

array1 中的值不在 array2 （更多）

array2 中的值不在 array1 (less)

array1 和 array2 中的值，但 不同 (diff)

//results for array1 (when it is in more, it is in array1 and not in array2. same for less)
function compare_multi_Arrays($array1, $array2){
    $result = array("more"=>array(),"less"=>array(),"diff"=>array());
    foreach($array1 as $k => $v) {
      if(is_array($v) && isset($array2[$k]) && is_array($array2[$k])){
        $sub_result = compare_multi_Arrays($v, $array2[$k]);
        //merge results
        foreach(array_keys($sub_result) as $key){
          if(!empty($sub_result[$key])){
            $result[$key] = array_merge_recursive($result[$key],array($k => $sub_result[$key]));
          }
        }
      }else{
        if(isset($array2[$k])){
          if($v !== $array2[$k]){
            $result["diff"][$k] = array("from"=>$v,"to"=>$array2[$k]);
          }
        }else{
          $result["more"][$k] = $v;
        }
      }
    }
    foreach($array2 as $k => $v) {
        if(!isset($array1[$k])){
            $result["less"][$k] = $v;
        }
    }
    return $result;
}