array_intersect_ukey

(PHP 5 >= 5.1.0)

array_intersect_ukey — Computes the intersection of arrays using a callback function on the keys for comparison

說明

array array_intersect_ukey ( array $array1 , array $array2 [, array $... ], callable $key_compare_func )

array_intersect_ukey() returns an array containing all the values of array1 which have matching keys that are present in all the arguments.

參數

array1: Initial array for comparison of the arrays.
array2: First array to compare keys against.
...: Variable list of array arguments to compare keys against.
key_compare_func: 在第一個參數小於、等於或大於第二個參數時，該比較函式必須相應地回傳一個小於、等於或大於 0 的整數。

int callback ( mixed $a, mixed $b )

回傳值

Returns the values of array1 whose keys exist in all the arguments.

範例

Example #1 array_intersect_ukey() example


<?php
function key_compare_func($key1, $key2)
{
    if ($key1 == $key2)
        return 0;
    else if ($key1 > $key2)
        return 1;
    else
        return -1;
}

$array1 = array('blue'  => 1, 'red'  => 2, 'green'  => 3, 'purple' => 4);
$array2 = array('green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan'   => 8);

var_dump(array_intersect_ukey($array1, $array2, 'key_compare_func'));
?>

上例將輸出：

array(2) {
  ["blue"]=>
  int(1)
  ["green"]=>
  int(3)
}

In our example you see that only the keys 'blue' and 'green' are present in both arrays and thus returned. Also notice that the values for the keys 'blue' and 'green' differ between the two arrays. A match still occurs because only the keys are checked. The values returned are those of array1.

參見

array_diff() - Computes the difference of arrays
array_udiff() - Computes the difference of arrays by using a callback function for data comparison
array_diff_assoc() - Computes the difference of arrays with additional index check
array_diff_uassoc() - Computes the difference of arrays with additional index check which is performed by a user supplied callback function
array_udiff_assoc() - Computes the difference of arrays with additional index check, compares data by a callback function
array_udiff_uassoc() - Computes the difference of arrays with additional index check, compares data and indexes by a callback function
array_diff_key() - Computes the difference of arrays using keys for comparison
array_diff_ukey() - Computes the difference of arrays using a callback function on the keys for comparison
array_intersect() - Computes the intersection of arrays
array_intersect_assoc() - Computes the intersection of arrays with additional index check
array_intersect_uassoc() - Computes the intersection of arrays with additional index check, compares indexes by a callback function
array_intersect_key() - Computes the intersection of arrays using keys for comparison

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User Contributed Notes 1 note

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gk at anuary dot com ¶

10 years ago


"array_intersect_ukey" will not work if $key_compare_func is using regular expression to perform comparison. "_array_intersect_ukey" fully implements the "array_intersect_ukey" interface and handles properly boolean comparison. However, the native implementation should be preferred for efficiency reasons.

<?php
$key_compare_func = function ($a, $b) {
    var_dump('a=' . $a. '; b=' . $b);
    
    if (strpos($b, '/') === 0) {
        return preg_match($b, $a) > 0 ? 0 : -1;
    }
    
    if ($a == $b) {
        $weight = 0;
    } else if ($a > $b) {
        $weight = 1;
    } else {
        $weight = -1;
    }
    
    var_dump('literal comparison: ' . $weight);
    
    return $weight;
};

$foo = ['aab' => '', 'bbb' => '', 'ccb' => '', 'abb' => ''];
$bar = ['/[a-z]b[a-z]/' => ''];
$buz = ['/c[a-z][a-z]/' => ''];

echo PHP_EOL . 'array_intersect_ukey' . PHP_EOL . PHP_EOL;

$subject = array_intersect_ukey ($foo, $bar, $buz, $key_compare_func);

echo PHP_EOL;

var_dump($subject);

echo PHP_EOL . '_array_intersect_ukey' . PHP_EOL . PHP_EOL;

$subject = _array_intersect_ukey($foo, $bar, $buz, $key_compare_func);

echo PHP_EOL;

var_dump($subject);

/**
 * @author Gajus Kuizinas <gk@anuary.com>
 * @version 1.0.0 (2013 09 30)
 * @url https://gist.github.com/gajus/271ad5f36337a32a184c
 */
function _array_intersect_ukey (array $arr1, array $arr2, $key_compare_func) {
    $arr_matched = [];
    $arr_unmatched = [];
    
    $args = func_get_args();
    
    $key_compare_func = end($args);
    
    foreach ($arr1 as $k1 => $v1) {
        foreach ($arr2 as $k2 => $v2) {
            $diff = $key_compare_func($k1, $k2);
        
            //var_dump('k1=' . $k1 . ', k2=' . $k2 . ', diff=' . $diff);
            
            if ($diff === 0) {
                $arr_matched[$k1] = $v1;
            } else {
                $arr_unmatched[$k1] = $v1;
            }
        }
    }
    
    if (count($args) <= 3) {
        return $arr_matched;
    }
    
    array_splice($args, 0, 2, [$arr_unmatched]);
    
    return array_merge($arr_matched, call_user_func_array('_array_intersect_ukey', $args));
}

/*
array_intersect_ukey

string(12) "a=bbb; b=aab"
string(21) "literal comparison: 1"
string(12) "a=bbb; b=ccb"
string(22) "literal comparison: -1"
string(12) "a=abb; b=bbb"
string(22) "literal comparison: -1"
string(12) "a=aab; b=abb"
string(22) "literal comparison: -1"
string(22) "a=aab; b=/[a-z]b[a-z]/"
string(22) "a=abb; b=/[a-z]b[a-z]/"
string(22) "a=abb; b=/c[a-z][a-z]/"

array(0) {
}

_array_intersect_ukey

string(22) "a=aab; b=/[a-z]b[a-z]/"
string(22) "a=bbb; b=/[a-z]b[a-z]/"
string(22) "a=ccb; b=/[a-z]b[a-z]/"
string(22) "a=abb; b=/[a-z]b[a-z]/"
string(22) "a=aab; b=/c[a-z][a-z]/"
string(22) "a=ccb; b=/c[a-z][a-z]/"

array(3) {
  ["bbb"]=>
  string(0) ""
  ["abb"]=>
  string(0) ""
  ["ccb"]=>
  string(0) ""
}*/
?>

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