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;
}
array_intersect_assoc
(PHP 4 >= 4.3.0, PHP 5)
array_intersect_assoc — Computes the intersection of arrays with additional index check
Description
array_intersect_assoc() returns an array containing all the values of array1 that are present in all the arguments. Note that the keys are used in the comparison unlike in array_intersect().
Parameters
- array1
-
The array with master values to check.
- array2
-
An array to compare values against.
- array
-
A variable list of arrays to compare.
Return Values
Returns an associative array containing all the values in array1 that are present in all of the arguments.
Examples
Example #1 array_intersect_assoc() example
<?php
$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "green", "yellow", "red");
$result_array = array_intersect_assoc($array1, $array2);
print_r($result_array);
?>
The above example will output:
Array ( [a] => green )
In our example you see that only the pair "a" => "green" is present in both arrays and thus is returned. The value "red" is not returned because in $array1 its key is 0 while the key of "red" in $array2 is 1.
The two values from the key => value pairs are considered equal only if (string) $elem1 === (string) $elem2 . In other words a strict type check is executed so the string representation must be the same.
array_intersect_assoc
20-Apr-2006 12:20
13-Oct-2005 08:34
To find the keys that are in 2 arrays, without caring of the values:
This is a function i needed, and it also returns the values of the first array
<?php
function array_key_intersect(&$a, &$b) {
$array = array();
while (list($key,$value) = each($a)) {
if (isset($b[$key]))
$array[$key] = $value;
}
return $array;
}
?>
14-Dec-2004 02:26
# 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
)
)
$result_array will look like:
(
a => green
)
11-Feb-2004 07:46
A combination of the two functions [array_intersect() and array_intersect_assoc()] in order to obtain the intersection of two multidimensional arrays.
<?php
function array_intersect_assoc_recursive(&$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;
}
?>
