array_diff -计算数组的差值

http://php.net/manual/en/function.array-diff.php

数组$array1，数组$array2[，数组$…]) 将array1与一个或多个其他数组进行比较，并返回array1中没有出现在任何其他数组中的值。

将它们与其他值进行比较:

if($array_a == $array_b) {
  //they are the same
}

你可以在这里阅读所有数组操作符: http://php.net/manual/en/language.operators.array.php 例如，请注意===还检查数组中元素的类型和顺序是否相同。

$arraysAreEqual = ($a == $b); // TRUE if $a and $b have the same key/value pairs.
$arraysAreEqual = ($a === $b); // TRUE if $a and $b have the same key/value pairs in the same order and of the same types.

参见数组操作符。

EDIT

不等式运算符是!=，而非恒等运算符是!==来匹配相等 运算符==和恒等运算符===。

尝试序列化。这也将检查嵌套子数组。

$foo =serialize($array_foo);
$bar =serialize($array_bar);
if ($foo == $bar) echo "Foo and bar are equal";

根据这一页。

注意:接受的答案适用于关联数组，但不适用于索引数组(下文解释)。如果你想比较它们中的任何一个，那么使用这个解决方案。此外，此函数可能不适用于多维数组(由于array_diff函数的性质)。

测试两个索引数组，其中元素的顺序不同，使用$a == $b或$a === $b会失败，例如:

<?php
    (array("x","y") == array("y","x")) === false;
?>

这是因为上面的意思是:

阵列(0 = > " x ", 1 = > " y ")和数组(0 = > " y ", 1 = > " x ")。

要解决这个问题，请使用:

<?php
function array_equal($a, $b) {
    return (
         is_array($a) 
         && is_array($b) 
         && count($a) == count($b) 
         && array_diff($a, $b) === array_diff($b, $a)
    );
}
?>

添加了比较数组大小(由super_ton建议)，因为它可以提高速度。

一种方法:(为https://www.rfc-editor.org/rfc/rfc6902#section-4.6实现“考虑平等”)

这种方式允许关联数组的成员顺序不同——例如，除了php，它们在每种语言中都被认为是相等的:)

// recursive ksort
function rksort($a) {
  if (!is_array($a)) {
    return $a;
  }
  foreach (array_keys($a) as $key) {
    $a[$key] = ksort($a[$key]);
  }
  // SORT_STRING seems required, as otherwise
  // numeric indices (e.g. "0") aren't sorted.
  ksort($a, SORT_STRING);
  return $a;
}


// Per https://www.rfc-editor.org/rfc/rfc6902#section-4.6
function considered_equal($a1, $a2) {
  return json_encode(rksort($a1)) === json_encode(rksort($a2));
}

另一种不考虑值顺序检查是否相等的方法使用http://php.net/manual/en/function.array-intersect.php，如下所示:

$array1 = array(2,5,3);
$array2 = array(5,2,3);
if($array1 === array_intersect($array1, $array2) && $array2 === array_intersect($array2, $array1)) {
    echo 'Equal';
} else {
    echo 'Not equal';
}

下面是一个使用http://php.net/manual/en/function.array-uintersect.php:也可以用于多维数组的版本

$array1 = array(
    array(5, 2),
    array(3, 6),
    array(2, 9, 4)
);
$array2 = array(
    array(3, 6),
    array(2, 9, 4),
    array(5, 2)
);

if($array1 === array_uintersect($array1, $array2, 'compare') && $array2 === array_uintersect($array2, $array1, 'compare')) {
    echo 'Equal';
} else {
    echo 'Not equal';
}

function compare($v1, $v2) {
    if ($v1===$v2) {
        return 0;
    }
    if ($v1 > $v2) return 1;
    return -1;
}

使用php函数array_diff(array1, array2);

它将返回数组之间的差值。如果是空的，那么它们相等。

例子:

$array1 = array(
    'a' => 'value1',

    'b' => 'value2',

    'c' => 'value3'
 );

$array2 = array(
    'a' => 'value1',

    'b' => 'value2',

    'c' => 'value4'
 );

$diff = array_diff(array1, array2);

var_dump($diff); 

//it will print array = (0 => ['c'] => 'value4' ) 

示例2:

$array1 = array(
    'a' => 'value1',

    'b' => 'value2',

    'c' => 'value3',
 );

$array2 = array(
    'a' => 'value1',

    'b' => 'value2',

    'c' => 'value3',
 );

$diff = array_diff(array1, array2);

var_dump($diff); 

//it will print empty; 

简单的解决方案，即使是数组的键以不同的顺序给出:

public static function arrays_are_equal($array1, $array2)
{
    array_multisort($array1);
    array_multisort($array2);
    return ( serialize($array1) === serialize($array2) );
}

数组的语法问题

$array1 = array(
    'a' => 'value1',
    'b' => 'value2',
    'c' => 'value3',
 );

$array2 = array(
    'a' => 'value1',
    'b' => 'value2',
    'c' => 'value3',
 );

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

var_dump($diff); 

if (array_diff($a,$b) == array_diff($b,$a)) {
  // Equals
}

if (array_diff($a,$b) != array_diff($b,$a)) {
  // Not Equals
}

从我的观点来看，最好使用array_diff而不是array_intersect，因为这种性质的检查通常返回的差异小于相似点，这样bool转换占用的内存更少。

注意，此解决方案适用于普通数组，并补充了上面发布的仅对字典有效的==和===。

如果你想检查非关联数组，下面是解决方案:

$a = ['blog', 'company'];
$b = ['company', 'blog'];

(count(array_unique(array_merge($a, $b))) === count($a)) ? 'Equals' : 'Not Equals';
// Equals

function compareIsEqualArray(array $array1,array $array2):bool
{

   return (array_diff($array1,$array2)==[] && array_diff($array2,$array1)==[]);

}

下面是如何比较数组并获得它们之间的不同之处的示例。

$array1 = ['1' => 'XXX', 'second' => [
            'a' => ['test' => '2'],
            'b' => 'test'
        ], 'b' => ['no test']];

        $array2 = [
            '1' => 'XX',
            'second' => [
                'a' => ['test' => '5', 'z' => 5],
                'b' => 'test'
            ],
            'test'
        ];


        function compareArrayValues($arrayOne, $arrayTwo, &$diff = [], $reversed = false)
        {
            foreach ($arrayOne as $key => $val) {
                if (!isset($arrayTwo[$key])) {
                    $diff[$key] = 'MISSING IN ' . ($reversed ? 'FIRST' : 'SECOND');
                } else if (is_array($val) && (json_encode($arrayOne[$key]) !== json_encode($arrayTwo[$key]))) {
                    compareArrayValues($arrayOne[$key], $arrayTwo[$key], $diff[$key], $reversed);
                } else if ($arrayOne[$key] !== $arrayTwo[$key]) {
                    $diff[$key] = 'DIFFERENT';
                }
            }
        }

        $diff = [];
        $diffSecond = [];

        compareArrayValues($array1, $array2, $diff);
        compareArrayValues($array2, $array1, $diffSecond, true);

        print_r($diff);
        print_r($diffSecond);

        print_r(array_merge($diff, $diffSecond));

结果:

Array
(
    [0] => DIFFERENT
    [second] => Array
        (
            [a] => Array
                (
                    [test] => DIFFERENT
                    [z] => MISSING IN FIRST
                )

        )

    [b] => MISSING IN SECOND
    [1] => DIFFERENT
    [2] => MISSING IN FIRST
)

下面的解决方案使用可作为回调传递的自定义相等函数。注意，它不检查数组的顺序。

trait AssertTrait
{
    /**
     * Determine if two arrays have the same elements, possibly in different orders. Elements comparison function must be passed as argument.
     *
     * @param array<mixed> $expected
     * @param array<mixed> $actual
     *
     * @throws InvalidArgumentException
     */
    public static function assertArraysContainSameElements(array $expected, array $actual, callable $comparisonFunction): void
    {
        Assert::assertEquals(\count($expected), \count($actual));

        self::assertEveryElementOfArrayIsInAnotherArrayTheSameAmountOfTimes($expected, $actual, $comparisonFunction);
        self::assertEveryElementOfArrayIsInAnotherArrayTheSameAmountOfTimes($actual, $expected, $comparisonFunction);
    }

    /**
     * @param array<mixed> $needles
     * @param array<mixed> $haystack
     *
     * @throws InvalidArgumentException
     */
    private static function assertEveryElementOfArrayIsInAnotherArrayTheSameAmountOfTimes(
        array $needles,
        array $haystack,
        callable $comparisonFunction
    ): void {
        Assert::assertLessThanOrEqual(\count($needles), \count($haystack));

        foreach ($needles as $expectedElement) {
            $matchesOfExpectedElementInExpected = \array_filter(
                $needles,
                static fn($element): bool => $comparisonFunction($expectedElement, $element),
            );

            $matchesOfExpectedElementInActual = \array_filter(
                $haystack,
                static fn($element): bool => $comparisonFunction($expectedElement, $element),
            );

            Assert::assertEquals(\count($matchesOfExpectedElementInExpected), \count($matchesOfExpectedElementInActual));
        }
    }
}

我通常在数据库集成测试中使用它，当我想确保返回预期的元素，但我不关心排序。

比较两个数组是否相等的正确方法是使用严格相等(===)，这是递归比较。现有的答案无法递归地对任意数组(具有任意深度和顺序的数组，包含顺序数组和关联数组的混合)进行排序，因此无法处理任意数组的比较。顺序数组是具有顺序键(0,1,2,3…)的关联数组，而关联数组没有顺序键。

要对这些任意数组排序，我们必须:

向下遍历没有更多子数组的叶节点 通过序列化顺序数组，然后排序它们(以消除必须使用自定义比较器的需要) 按键对关联数组排序

下面的代码实现了上述解决方案。欢迎对代码进行改进。

function recur_sort( &$array ) {
    foreach ( $array as &$value ) {
       if ( is_array( $value ) ) recur_sort( $value );
    }

    if ( is_sequential_array( $array ) ) {
        $array = array_map( function( $el ) { return json_encode( $el ); }, $array  );
        sort( $array, SORT_STRING );
        $array = array_map( function( $el ) { return json_decode( $el, true ); }, $array  );
        return;
    } else {
        return ksort( $array );
    }
}

function is_sequential_array(Array &$a) {
    $n = count($a);
    for($i=0; $i<$n; $i++) {
        if(!array_key_exists($i, $a)) {
            return false;
        }
    }
    return true;
}

示例(在PHPUnit中):

//A stricter and recursive assertEqualsCanonicalizing
public function assertSameCanonicalizing( $expected, $actual ) {
    recur_sort( $expected );
    recur_sort( $actual );
    $this->assertSame( $expected, $actual );
}

如果你想检查数组的键和值是否严格相等(===)，你可以使用下面的函数:

function array_eq($a, $b) {
    // If the objects are not arrays or differ in their size, they cannot be equal
    if (!is_array($a) || !is_array($b) || count($a) !== count($b)) {
        return false;
    }
    // If the arrays of keys are not strictly equal (after sorting),
    // the original arrays are not strictly equal either
    $a_keys = array_keys($a);
    $b_keys = array_keys($b);
    array_multisort($a_keys);
    array_multisort($b_keys);
    if ($a_keys !== $b_keys) {
        return false;
    }
    // Comparing values
    foreach ($a_keys as $key) {
        $a_value = $a[$key];
        $b_value = $b[$key];
        // Either the objects are strictly equal or they are arrays
        // which are equal according to our definition. Otherwise they
        // are different.
        if ($a_value !== $b_value && !array_eq($a_value, $b_value)) {
            return false;
        }
    }
    return true;
}

比较你的数组的值，也是多维的，关联的和任意组合的:

/**
 * @see PHPUnit Assert::assertEqualsCanonicalizing()
 * @return true if all keys and values are equal and of the same type,
 * irregardless of items or keys order
 */
function array_vals_equal(array $a, array $b): bool {
    // sort multi-dimensional recursive
    $_deep_sort = function (array $a) use (&$_deep_sort): array{
        // sort discarding index association or sort keys, depending on array type
        array_is_list($a) ? sort($a) : ksort($a);
        return array_map(fn($v) => is_array($v) ? $_deep_sort($v) : $v, $a);
    };
    // operator === checks that the count, types and order of the elements are the same
    return $_deep_sort($a) === $_deep_sort($b);
}

// Test cases
assertEquals(array_vals_equal([1], [1]), true, 'simple eq');
assertEquals(array_vals_equal([0], [false]), false, 'simple eq');
assertEquals(array_vals_equal([0], [null]), false, 'simple eq');
assertEquals(array_vals_equal([0, 1], [1, 0]), true, 'simple eq, diff order');
assertEquals(array_vals_equal([0, 1, 2], [1, 0]), false, 'diff count');
assertEquals(array_vals_equal([0, 1], [0, 1, 2]), false, 'diff count 2');
assertEquals(array_vals_equal([1, 2], [1, 2, 'hello']), false, 'diff count 3');
//
assertEquals(array_vals_equal([1, 2, 2], [2, 1, 1]), false, 'same vals repeated');
assertEquals(array_vals_equal([1, 2, 2], [2, 2, 1]), true, 'same vals, different order');
//
assertEquals(array_vals_equal([1, 2, 3], ['1', '2', '3']), false, 'int should not be eq string');
assertEquals(array_vals_equal([0 => 'a', 1 => 'b'], [0 => 'b', 1 => 'a']), true, 'same vals, diff order');
assertEquals(array_vals_equal(['a', 'b'], [3 => 'b', 5 => 'a']), true, 'same vals, diff indexes');
// associative arrays whose members are ordered differently
assertEquals(array_vals_equal(['aa' => 'a', 'bb' => 'b'], ['bb' => 'b', 'aa' => 'a']), true, 'dict with different order');
assertEquals(array_vals_equal(['aa' => 'a', 'bb' => 'b'], ['aa' => 'a']), false, 'a key is missing');
assertEquals(array_vals_equal(['aa' => 'a', 'bb' => 'b'], ['aa' => 'a', 'zz' => 'b']), false, 'dict same vals diff key');
// nested arrays with keys in different order
assertEquals(array_vals_equal(
    ['aa' => 'a', 'bb' => ['bb' => 'b', 'aa' => 'a']],
    ['aa' => 'a', 'bb' => ['aa' => 'a', 'bb' => 'b']]
), true, 'dict multi 2 level, keys in different order');
assertEquals(array_vals_equal(
    ['aa' => 'a', 'bb' => ['aa2' => 'a', 'bb2' => ['aa3' => 'a', 'bb3' => 'b']]],
    ['aa' => 'a', 'bb' => ['aa2' => 'a', 'bb2' => ['aa3' => 'a', 'bb3' => 'b']]]
), true, 'dict multi 3 level');
assertEquals(array_vals_equal(
    ['aa' => 'a', 'bb' => [0, 1]],
    ['aa' => 'a', 'bb' => [1, 0]]
), true, 'dict multi level, 2^ level sequential in different order');
assertEquals(array_vals_equal([[0, 1], ['a', 'b']], [['b', 'a'], [1, 0]]), true, 'multi level sequential');

如果你想生成一份详细的报告，你可以使用这样的东西:

function deepCompare(Array $a, Array $b, string $parentAKey, string $parentBKey, bool $compareInverted = true, bool $compareValues = true, string $log = '')
{
    foreach ($a as $aKey => $aValue) {
        $fullAKey = implode('.', [$parentAKey, $aKey]);
        $fullBKey = implode('.', [$parentBKey, $aKey]);
        if (! isset($b[$aKey])) {
            $log .= "⍰ {$fullAKey} has no equivalent {$fullBKey}\n";
        } else {
            $bValue = $b[$aKey];
            if (is_array($aValue)) {
                $log = deepCompare($aValue, $bValue, $fullAKey, $fullBKey, false, $compareValues, $log);
            } else {
              if ($compareValues) {
                  if ($aValue != $bValue) {
                      $log .= "≠ {$fullAKey} value differs from {$fullBKey}\n";
                  }
              }
            }
        }
    }
    if ($compareInverted) {
        $log = deepCompare($b, $a, $parentBKey, $parentAKey, false, false, $log);
    }
    return $log;
}

下面是一个例子:

$november = [
  'site1' => [
    'id' => 15,
    'name' => 'Brazil',
    'extendedHours' => 454,
  ],
  'site2' => [
    'id' => 43,
    'name' => 'Portugal',
    'extendedHours' => 448,
  ],
  'site3' => [
    'id' => 49,
    'name' => 'Spain',
    'extendedHours' => 0,
  ],  
  'totalExtendedHours' => 902,
];

$december = [
  'site1' => [
    'id' => 15,
    'name' => 'Brazil',
    'extendedHours' => 498,
  ],
  'site2' => [
    'id' => 43,
    'name' => 'Portugal',
    'extendedHours' => 409,
    'extraRequests' => 6,
  ],
  'totalExtendedHours' => 907,
  'totalExtraRequests' => 6,
];

echo deepCompare(
    $november,    -- origin array
    $december,    -- target array
    'Nov2022',    -- descriptive name of origin array
    'Dec2022',    -- descriptive name of target array
    true,         -- should also compare arrays in reverse order?
    true          -- should care about array values? (false = names only)
);

这个例子将输出:

≠ Nov2022.site1.extendedHours value differs from Dec2022.site1.extendedHours
≠ Nov2022.site2.extendedHours value differs from Dec2022.site2.extendedHours
⍰ Nov2022.site3 has no equivalent Dec2022.site3
≠ Nov2022.totalExtendedHours value differs from Dec2022.totalExtendedHours
⍰ Dec2022.site2.extraRequests has no equivalent Nov2022.site2.extraRequests
⍰ Dec2022.totalExtraRequests has no equivalent Nov2022.totalExtraRequests

我希望这能帮助到一些人。