array_intersect_ukey

(PHP 5 >= 5.1.0, PHP 7)

array_intersect_ukey用回调函数比较键名来计算数组的交集

说明

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

array_intersect_ukey() 返回一个数组,该数组包含了所有出现在 array1 中并同时出现在所有其它参数数组中的键名的值。

参数

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

在第一个参数小于,等于或大于第二个参数时,该比较函数必须相应地返回一个小于,等于或大于 0 的整数。

callback ( mixed $a, mixed $b ) : int

返回值

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

范例

Example #1 array_intersect_ukey() 例子

<?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'));
?>

以上例程会输出:

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

上例中可以看到只有 'blue''green' 两个键名出现在两个数组中,因此被返回。此外注意 'blue''green' 的值在两个数组中是不同的。但因为只检查键名,因此还是匹配。返回的值只是 array1 中的。

参见

User Contributed Notes

gk at anuary dot com 30-Sep-2013 04:52
"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) ""
}*/
?>