两个数组的区别答案

【问题标题】：difference between two arrays两个数组的区别
【发布时间】：2012-04-09 18:25:30
【问题描述】：

我有以下两个数组。我想要这两个数组之间的区别。也就是如何找到两个数组中都不存在的值？

 $array1=Array ( [0] => 64 [1] => 98 [2] => 112 [3] => 92 [4] => 92 [5] => 92 ) ;
 $array2=Array ( [0] => 3 [1] => 26 [2] => 38 [3] => 40 [4] => 44 [5] => 46 [6] => 48 [7] => 52 [8] => 64 [9] => 68 [10] => 70 [11] => 72 [12] => 102 [13] => 104 [14] => 106 [15] => 92 [16] => 94 [17] => 96 [18] => 98 [19] => 100 [20] => 108 [21] => 110 [22] => 112);

【问题讨论】：

标签： php

【解决方案1】：

要获得两个数组之间的差异，您需要执行以下操作：

$fullDiff = array_merge(array_diff($array1, $array2), array_diff($array2, $array1));

原因是array_diff() 只会给你$array1 中的值而不是$array2，而不是相反。以上将为您提供两者。

【讨论】：

如需维护密钥：$full_diff = array_diff($array1, $array2) + array_diff($array2, $array1);

【解决方案2】：

注意：此答案将返回$array2 中不存在于$array1 中的值，它不会返回$array1 中不存在于$array2 中的值。

$diff = array_diff($array2, $array1);

array_diff()

【讨论】：

这似乎不正确 - 它不会从 $array2 返回 $array1 中不存在的值。 Crasherspeeder 似乎是对的。
@Crasherspeeder 是正确的，这是一个单向检查 - 提问者想要两者。
array_diff_* 系列还为多维数组抛出“ErrorException: Array to string conversion”。

【解决方案3】：

如果你想递归获取数组之间的差异，试试这个函数：

function arrayDiffRecursive($firstArray, $secondArray, $reverseKey = false)
{
    $oldKey = 'old';
    $newKey = 'new';
    if ($reverseKey) {
        $oldKey = 'new';
        $newKey = 'old';
    }
    $difference = [];
    foreach ($firstArray as $firstKey => $firstValue) {
        if (is_array($firstValue)) {
            if (!array_key_exists($firstKey, $secondArray) || !is_array($secondArray[$firstKey])) {
                $difference[$oldKey][$firstKey] = $firstValue;
                $difference[$newKey][$firstKey] = '';
            } else {
                $newDiff = arrayDiffRecursive($firstValue, $secondArray[$firstKey], $reverseKey);
                if (!empty($newDiff)) {
                    $difference[$oldKey][$firstKey] = $newDiff[$oldKey];
                    $difference[$newKey][$firstKey] = $newDiff[$newKey];
                }
            }
        } else {
            if (!array_key_exists($firstKey, $secondArray) || $secondArray[$firstKey] != $firstValue) {
                $difference[$oldKey][$firstKey] = $firstValue;
                $difference[$newKey][$firstKey] = $secondArray[$firstKey];
            }
        }
    }
    return $difference;
}

测试：

$differences = array_replace_recursive(
    arrayDiffRecursive($firstArray, $secondArray),
    arrayDiffRecursive($secondArray, $firstArray, true)
);
var_dump($differences);

【讨论】：

网络上php的最佳递归数组差异
出色的工作这是每个人都在寻找的。span>

【解决方案4】：

array_diff?

http://php.net/array_diff

var_dump(array_diff($array2, $array1));

【讨论】：

【解决方案5】：

<?php
function getArrayDiff($a1, $a2) {
    $result = array();

    print_r($a1);
    print_r($a2);

    // If First Array is Bigger than Second
    if( count($a1) > count($a2) ) {
        $result=array_diff($a1,$a2);
    }
    // If Second Array is Bigger than First
    if( count($a1) < count($a2) ) {
        $result=array_diff($a2,$a1);
    }
    // If Both array are same but, data values are different.
    else
    {
        $result = array_merge (array_diff($a2,$a1), array_diff($a1,$a2));   
    }
    return $result;
}

print "<pre>";
// First Array is Big
echo "First Array is Big <br/>";
$a1=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow");
$a2=array("e"=>"red","f"=>"green","g"=>"blue");
print_r( getArrayDiff($a1, $a2) );

// Second Array is Big
echo "Second Array is Big <br/>";
$a1=array("e"=>"red","f"=>"green","g"=>"blue");
$a2=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow");
print_r( getArrayDiff($a1, $a2) );

// Both Array are same
echo "Both Array are same <br/>";
$a1=array("a"=>"red","b"=>"green","d"=>"yellow");
$a2=array("e"=>"red","f"=>"green","g"=>"blue");
print_r( getArrayDiff($a1, $a2) );

?>

输出：

First Array is Big 
Array
(
    [a] => red
    [b] => green
    [c] => blue
    [d] => yellow
)
Array
(
    [e] => red
    [f] => green
    [g] => blue
)
Array
(
    [d] => yellow
)
Second Array is Big 
Array
(
    [e] => red
    [f] => green
    [g] => blue
)
Array
(
    [a] => red
    [b] => green
    [c] => blue
    [d] => yellow
)
Array
(
    [d] => yellow
)
Both Array are same 
Array
(
    [a] => red
    [b] => green
    [d] => yellow
)
Array
(
    [e] => red
    [f] => green
    [g] => blue
)
Array
(
    [g] => blue
    [d] => yellow
)

【讨论】：

【解决方案6】：

如果你打算使用array_diff()。
需要记住的是，参数的编写顺序。

PHP 文档：array_diff

# array_diff(1, 2)
array_diff($one, $two);

# array_diff(2, 1)
array_diff($two, $one); // produces different result.

【讨论】：