array_udiff

说明

array array_udiff ( array array1, array array2 [, array ..., callback data_compare_func] )

array_udiff() 返回一个数组，该数组包括了所有在 array1 中但是不在任何其它参数数组中的值。注意键名保持不变。数据的比较是用 data_compare_func 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。这和 array_diff() 不同，后者使用了内部函数来比较数据。

例子 1. array_udiff() 例子
<?php class cr { private $priv_member; function cr($val) { $this->priv_member = $val; } function comp_func_cr($a, $b) { if ($a->priv_member === $b->priv_member) return 0; return ($a->priv_member > $b->priv_member)? 1:-1; } } $a = array("0.1" => new cr(9), "0.5" => new cr(12), 0 => new cr(23), 1=> new cr(4), 2 => new cr(-15),); $b = array("0.2" => new cr(9), "0.5" => new cr(22), 0 => new cr(3), 1=> new cr(4), 2 => new cr(-15),); $result = array_udiff($a, $b, array("cr", "comp_func_cr")); print_r($result); ?>
上例将输出：
Array ( [0.5] => cr Object ( [priv_member:private] => 12 ) [0] => cr Object ( [priv_member:private] => 23 ) )

注: 注意本函数只检查了多维数组中的一维。当然，可以用 array_udiff($array1[0], $array2[0], "data_compare_func"); 来检查更深的维度。

参见 array_diff()，array_diff_assoc()，array_diff_uassoc()，array_udiff_assoc()，array_udiff_uassoc()，array_intersect()，array_intersect_assoc()，array_uintersect()，array_uintersect_assoc() 和 array_uintersect_uassoc()。

add a note User Contributed Notes

dmhouse at gmail dot com
21-Jan-2005 05:44


Very easy way of achieving a case-insensitive version of array_diff (or indeed array_diff_assoc, array_intersect or any of these types of functions which have a similar function that takes a callback function as one of their parameters):



array_udiff($array1, $array2, 'strcasecmp');



This works because strcasecmp() compares two strings case-insensitively, as compared to the array_diff() which compares two strings by using the == operator, which is case-sensitive.

aidan at php dot net
28-May-2004 10:11


This functionality is now implemented in the PEAR package PHP_Compat.



More information about using this function without upgrading your version of PHP can be found on the below link:



http://pear.php.net/package/PHP_Compat

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