This is one stop global knowledge base where you can learn about all the products, solutions and support features.
(PHP 5, PHP 7, PHP 8)
array_udiff — Computes the difference of arrays by using a callback function for data comparison
array_udiff(array $array, array ...$arrays, callable $value_compare_func): array
Computes the difference of arrays by using a callback function for data comparison. This is unlike array_diff() which uses an internal function for comparing the data.
array
The first array.
arrays
Arrays to compare against.
value_compare_func
The callback comparison function.
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed $a, mixed $b): int
Returns an array containing all the values of
array
that are not present in any of the other arguments.
Example #1 array_udiff() example using stdClass Objects
<?php
// Arrays to compare
$array1 = array(new stdclass, new stdclass,
new stdclass, new stdclass,
);
$array2 = array(
new stdclass, new stdclass,
);
// Set some properties for each object
$array1[0]->width = 11; $array1[0]->height = 3;
$array1[1]->width = 7; $array1[1]->height = 1;
$array1[2]->width = 2; $array1[2]->height = 9;
$array1[3]->width = 5; $array1[3]->height = 7;
$array2[0]->width = 7; $array2[0]->height = 5;
$array2[1]->width = 9; $array2[1]->height = 2;
function compare_by_area($a, $b) {
$areaA = $a->width * $a->height;
$areaB = $b->width * $b->height;
if ($areaA < $areaB) {
return -1;
} elseif ($areaA > $areaB) {
return 1;
} else {
return 0;
}
}
print_r(array_udiff($array1, $array2, 'compare_by_area'));
?>
The above example will output:
Array
(
[0] => stdClass Object
(
[width] => 11
[height] => 3
)
[1] => stdClass Object
(
[width] => 7
[height] => 1
)
)
Example #2 array_udiff() example using DateTime Objects
<?php
class MyCalendar {
public $free = array();
public $booked = array();
public function __construct($week = 'now') {
$start = new DateTime($week);
$start->modify('Monday this week midnight');
$end = clone $start;
$end->modify('Friday this week midnight');
$interval = new DateInterval('P1D');
foreach (new DatePeriod($start, $interval, $end) as $freeTime) {
$this->free[] = $freeTime;
}
}
public function bookAppointment(DateTime $date, $note) {
$this->booked[] = array('date' => $date->modify('midnight'), 'note' => $note);
}
public function checkAvailability() {
return array_udiff($this->free, $this->booked, array($this, 'customCompare'));
}
public function customCompare($free, $booked) {
if (is_array($free)) $a = $free['date'];
else $a = $free;
if (is_array($booked)) $b = $booked['date'];
else $b = $booked;
if ($a == $b) {
return 0;
} elseif ($a > $b) {
return 1;
} else {
return -1;
}
}
}
// Create a calendar for weekly appointments
$myCalendar = new MyCalendar;
// Book some appointments for this week
$myCalendar->bookAppointment(new DateTime('Monday this week'), "Cleaning GoogleGuy's apartment.");
$myCalendar->bookAppointment(new DateTime('Wednesday this week'), "Going on a snowboarding trip.");
$myCalendar->bookAppointment(new DateTime('Friday this week'), "Fixing buggy code.");
// Check availability of days by comparing $booked dates against $free dates
echo "I'm available on the following days this week...\n\n";
foreach ($myCalendar->checkAvailability() as $free) {
echo $free->format('l'), "\n";
}
echo "\n\n";
echo "I'm busy on the following days this week...\n\n";
foreach ($myCalendar->booked as $booked) {
echo $booked['date']->format('l'), ": ", $booked['note'], "\n";
}
?>
The above example will output:
I'm available on the following days this week... Tuesday Thursday I'm busy on the following days this week... Monday: Cleaning GoogleGuy's apartment. Wednesday: Going on a snowboarding trip. Friday: Fixing buggy code.
Note : Please note that this function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using
array_udiff($array1[0], $array2[0], "data_compare_func");.
(PHP 5, PHP 7, PHP 8)
array_udiff_assoc — Computes the difference of arrays with additional index check, compares data by a callback function
array_udiff_assoc(array $array, array ...$arrays, callable $value_compare_func): array
Computes the difference of arrays with additional index check, compares data by a callback function.
Note : Please note that this function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using, for example,
array_udiff_assoc($array1[0], $array2[0], "some_comparison_func");.
array
The first array.
arrays
Arrays to compare against.
value_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed $a, mixed $b): int
array_udiff_assoc()
returns an
array
containing all the values from
array
that are not present in any of the other arguments. Note that the keys are used in the comparison unlike
array_diff()
and
array_udiff()
. The comparison of arrays' data is performed by using an user-supplied callback. In this aspect the behaviour is opposite to the behaviour of
array_diff_assoc()
which uses internal function for comparison.
Example #1 array_udiff_assoc() example
<?php
class cr {
private $priv_member;
function __construct($val)
{
$this->priv_member = $val;
}
static function comp_func_cr($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),);
$result = array_udiff_assoc($a, $b, array("cr", "comp_func_cr"));
print_r($result);
?>
The above example will output:
Array
(
[0.1] => cr Object
(
[priv_member:private] => 9
)
[0.5] => cr Object
(
[priv_member:private] => 12
)
[0] => cr Object
(
[priv_member:private] => 23
)
)
In our example above you see the
"1" => new cr(4)
pair is present in both arrays and thus it is not in the output from the function.
(PHP 5, PHP 7, PHP 8)
array_udiff_uassoc — Computes the difference of arrays with additional index check, compares data and indexes by a callback function
array_udiff_uassoc( array $array, array ...$arrays, callable $value_compare_func, callable $key_compare_func ): array
Computes the difference of arrays with additional index check, compares data and indexes by a callback function.
Note that the keys are used in the comparison unlike array_diff() and array_udiff() .
array
The first array.
arrays
Arrays to compare against.
value_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed $a, mixed $b): int
key_compare_func
The comparison of keys (indices) is done also by the callback function
key_compare_func
. This behaviour is unlike what
array_udiff_assoc()
does, since the latter compares the indices by using an internal function.
Returns an
array
containing all the values from
array
that are not present in any of the other arguments.
Example #1 array_udiff_uassoc() example
<?php
class cr {
private $priv_member;
function __construct($val)
{
$this->priv_member = $val;
}
static function comp_func_cr($a, $b)
{
if ($a->priv_member === $b->priv_member) return 0;
return ($a->priv_member > $b->priv_member)? 1:-1;
}
static function comp_func_key($a, $b)
{
if ($a === $b) return 0;
return ($a > $b)? 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),);
$result = array_udiff_uassoc($a, $b, array("cr", "comp_func_cr"), array("cr", "comp_func_key"));
print_r($result);
?>
The above example will output:
Array
(
[0.1] => cr Object
(
[priv_member:private] => 9
)
[0.5] => cr Object
(
[priv_member:private] => 12
)
[0] => cr Object
(
[priv_member:private] => 23
)
)
In our example above you see the
"1" => new cr(4)
pair is present in both arrays and thus it is not in the output from the function. Keep in mind that you have to supply 2 callback functions.
Note : Please note that this function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using, for example,
array_udiff_uassoc($array1[0], $array2[0], "data_compare_func", "key_compare_func");.
(PHP 5, PHP 7, PHP 8)
array_uintersect — Computes the intersection of arrays, compares data by a callback function
array_uintersect(array $array, array ...$arrays, callable $value_compare_func): array
Computes the intersection of arrays, compares data by a callback function.
array
The first array.
arrays
Arrays to compare against.
value_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed $a, mixed $b): int
Returns an array containing all the values of
array
that are present in all the arguments.
Example #1 array_uintersect() example
<?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"));
?>
The above example will output:
Array
(
[a] => green
[b] => brown
[0] => red
)
(PHP 5, PHP 7, PHP 8)
array_uintersect_assoc — Computes the intersection of arrays with additional index check, compares data by a callback function
array_uintersect_assoc(array $array, array ...$arrays, callable $value_compare_func): array
Computes the intersection of arrays with additional index check, compares data by a callback function.
Note that the keys are used in the comparison unlike in array_uintersect() . The data is compared by using a callback function.
array
The first array.
arrays
Arrays to compare against.
value_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed $a, mixed $b): int
Returns an array containing all the values of
array
that are present in all the arguments.
Example #1 array_uintersect_assoc() example
<?php
$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "GREEN", "B" => "brown", "yellow", "red");
print_r(array_uintersect_assoc($array1, $array2, "strcasecmp"));
?>
The above example will output:
Array
(
[a] => green
)
(PHP 5, PHP 7, PHP 8)
array_uintersect_uassoc — Computes the intersection of arrays with additional index check, compares data and indexes by separate callback functions
array_uintersect_uassoc( array $array1, array ...$arrays, callable $value_compare_func, callable $key_compare_func ): array
Computes the intersection of arrays with additional index check, compares data and indexes by separate callback functions.
array1
The first array.
arrays
Further arrays.
value_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed $a, mixed $b): int
key_compare_func
Key comparison callback function.
Returns an array containing all the values of
array1
that are present in all the arguments.
Example #1 array_uintersect_uassoc() example
<?php
$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "GREEN", "B" => "brown", "yellow", "red");
print_r(array_uintersect_uassoc($array1, $array2, "strcasecmp", "strcasecmp"));
?>
The above example will output:
Array
(
[a] => green
[b] => brown
)