我想检查两个数组是否相等。我的意思是:相同的大小,相同的索引,相同的值。我该怎么做呢?

根据用户的建议使用!==,如果数组中至少有一个元素是不同的,我希望下面的代码会打印enter,但实际上并不是这样。

if (($_POST['atlOriginal'] !== $oldAtlPosition) 
    or ($_POST['atl'] !== $aext) 
    or ($_POST['sidesOriginal'] !== $oldSidePosition) 
    or ($_POST['sidesOriginal'] !== $sideext)) {

    echo "enter";
}

当前回答

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); 

其他回答

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;
}

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。

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); 

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');