array_intersect_assoc

(PHP 4 >= 4.3.0, PHP 5)

array_intersect_assoc -- 带索引检查计算数组的交集

说明

array array_intersect_assoc ( array array1, array array2 [, array ...] )

array_intersect_assoc() 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。注意和 array_intersect() 不同的是键名也用于比较。

例子 1. array_intersect_assoc() 例子

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

$result_array 将是:

Array
(
    [a] => green
)

上面例子中可以看到只有键值对 "a" => "green" 在两个数组中都存在从而被返回。值 "red" 没有被返回是因为在 $array1 中它的键名是 0 而在 $array2"red" 的键名是 1

键值对 key => value 中的两个值仅在 (string) $elem1 === (string) $elem2 时被认为相等。也就是说使用了严格检查,字符串的表达必须相同。

参见 array_intersect()array_uintersect_assoc()array_intersect_uassoc()array_uintersect_uassoc()array_diff()array_diff_assoc()


add a note add a note User Contributed Notes
asharm4 at ilstu dot edu
21-Apr-2006 12:20
A function to find intersection of two arrays when comparison is based on only 1 key

function array_common($array1,$array2,$compareString) {
   if (!is_array($array1) || !is_array($array2)) {
       return false;
   }
   $arrResult = array();
   foreach ($array1 as $arrInsideArray1) {
       foreach ($array2 as $arrInsideArray2) {
           $found=false;
           if ($arrInsideArray1[$compareString]==$arrInsideArray2[$compareString]) {
               $found=true;
               break;
           }
       }
       if ($found) {
           array_push($arrResult,$arrInsideArray1);
       }

   }
   return $arrResult;
}
StR: str at strgt dot cjb dot net
14-Oct-2005 08:34
To find the keys that are in 2 arrays, without caring of the values:

This is a function i needed, and it also returns the values of the first array

<?php
function array_key_intersect(&$a, &$b) {
 
$array = array();
  while (list(
$key,$value) = each($a)) {
   if (isset(
$b[$key]))
    
$array[$key] = $value;
  }
  return
$array;
}
?>
vandor at progressive dot hu
15-Dec-2004 03:26
# ket tomb kulcs alapu metszetet szamitja ki, az erteken is ellenorzest vegez
#
# calculating (key base) intersection of arrays (value are checked)
# use: $result_array = array_intersect_assoc($a1, $a2, $a3,..);
#
##
# original code by [jochem at iamjochem dawt com] : array_diff_keys()

<?php
function array_intersect_assoc() {

  
$args = func_get_args();
  
$res = $args[0];

   for (
$i=1;$i<count($args);$i++) {
       if (!
is_array($args[$i])) {continue;}

       foreach (
$res as $key => $data) {
           if ( (!
array_key_exists($key, $args[$i])) || ( (isset($args[$i][$key])) && ($args[$i][$key] !== $res[$key]) ) ) {
               unset(
$res[$key]);
           }
       }
   }

   return
$res;
}

?>

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

$result_array = array_intersect_assoc($a, $b, $array1, $array2);
?>

$args array will look like:

(
   0 =>
       (
           a => green
           b => brown
           c => yellow
       )

   1 =>
       (
           a => green
           b => brown
           c => yellow
           e => yellow
       )

   2 =>
       (
           a => green
           b => brown
           c => blue
           0 => red
       )

   3 =>
       (
           a => green
           b => yellow
           c => yellow
           0 => red
       )

)

$result_array will look like:

(
   a => green
)
nleippe at integr8ted dot com
12-Feb-2004 08:46
A combination of the two functions [array_intersect() and array_intersect_assoc()] in order to obtain the intersection of two multidimensional arrays.

<?php
function array_intersect_assoc_recursive(&$arr1, &$arr2) {
   if (!
is_array($arr1) || !is_array($arr2)) {
       return
$arr1 == $arr2; // or === for strict type
  
}
  
$commonkeys = array_intersect(array_keys($arr1), array_keys($arr2));
  
$ret = array();
   foreach (
$commonkeys as $key) {
      
$ret[$key] =& array_intersect_assoc_recursive($arr1[$key], $arr2[$key]);
   }
   return
$ret;
}
?>