array_uintersect

(PHP 5, PHP 7)

array_uintersect计算数组的交集,用回调函数比较数据

说明

array_uintersect ( array $array1 , array $array2 [, array $... ], callable $value_compare_func ) : array

array_uintersect() 返回一个数组,该数组包含了所有在 array1 中也同时出现在所有其它参数数组中的值。数据比较是用回调函数进行的。 此比较是通过用户提供的回调函数来进行的。如果认为第一个参数小于,等于,或大于第二个参数时必须分别返回一个小于零,等于零,或大于零的整数。

参数

array1

第一个数组。

array2

第二个数组。

value_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 an array containing all the values of array1 that are present in all the arguments.

范例

Example #1 array_uintersect() 例子

<?php
$array1 
= array("a" => "green""b" => "brown""c" => "blue""red");
$array2 = array("a" => "GREEN""B" => "brown""yellow""red");

print_r(array_uintersect($array1$array2"strcasecmp"));
?>

以上例程会输出:

Array
(
    [a] => green
    [b] => brown
    [0] => red
)

参见

User Contributed Notes

rob dot c dot ruiz at gmail dot com 15-Nov-2018 11:21
When trying to do a case insensitive comparison between arrays of words, the strcasecmp function works very nicely with this one like so:

$arr1 = array('blue', 'green', 'red');

$arr2 = array('BLUE', 'Purple', 'Red');

$loose_matches = array_uintersect($arr1, $arr2, 'strcasecmp');

print_r($loose_matches) // array('blue', 'red');
Hayley Watson 01-Jan-2018 10:25
As for the other "compare function" callbacks, the return value from the callback function doesn't need to be -1, 0, or 1.

cmp($a,$b) just needs to be <0, =0, or >0 depending on whether $a<$b, $a=$b, or $a>$b.
Nate at RuggFamily dot com 02-Feb-2007 12:03
I want to stress that in the user function, you do need to return either a 1 or a -1 properly; you cannot simply return 0 if the results are equal and 1 if they are not. 

The following code is incorrect:

<?php
function myfunction($v1,$v2)
{
if (
$v1===$v2)
    {
    return
0;
    }
return
1;
}

$a1=array(1, 2, 4);
$a2=array(1, 3, 4);
print_r(array_uintersect($a1,$a2,"myfunction"));
?>

This code is correct:

<?php
function myfunction($v1,$v2)
{
if (
$v1===$v2)
    {
    return
0;
    }
if (
$v1 > $v2) return 1;
return -
1;
}
$a1=array(1, 2, 4);
$a2=array(1, 3, 4);
print_r(array_uintersect($a1,$a2,"myfunction"));
?>