I have two arrays like this:
array(
'11' => '11',
'22' => '22',
'33' => '33',
'44' => '44'
);
array(
'44' => '44',
'55' => '55',
'66' => '66',
'77' => '77'
);
I want to combine these two array such that it does not contains duplicate and as well as keep their original keys. For example output should be:
array(
'11' => '11',
'22' => '22',
'33' => '33',
'44' => '44',
'55' => '55',
'66' => '66',
'77' => '77'
);
I have tried this but it is changing their original keys:
$output = array_unique( array_merge( $array1 , $array2 ) );
Any solution?
https://www.php.net/manual/en/function.array-merge.php
<?php
$array1 = array("color" => "red", 2, 4);
$array2 = array("a", "b", "color" => "green", "shape" => "trapezoid", 4);
$result = array_merge($array1, $array2);
print_r($result);
?>
This works:
$output = $array1 + $array2;
This works:
$a = array(1 => 1, 2 => 2, 3 => 3);
$b = array(4 => 4, 5 => 5, 6 => 6);
$c = $a + $b;
print_r($c);
The new way of doing it with php7.4 is Spread operator [...]
$parts = ['apple', 'pear'];
$fruits = ['banana', 'orange', ...$parts, 'watermelon'];
var_dump($fruits);
Spread operator should have better performance than array_merge
A significant advantage of Spread operator is that it supports any traversable objects, while the array_merge function only supports arrays.
You should take to consideration that $array1 + $array2 != $array2 + $array1
$array1 = array(
'11' => 'x1',
'22' => 'x1'
);
$array2 = array(
'22' => 'x2',
'33' => 'x2'
);
with $array1 + $array2
$array1 + $array2 = array(
'11' => 'x1',
'22' => 'x1',
'33' => 'x2'
);
and with $array2 + $array1
$array2 + $array1 = array(
'11' => 'x1',
'22' => 'x2',
'33' => 'x2'
);
If you are using PHP 7.4 or above, you can use the spread operator ...
as the following examples from the PHP Docs:
$arr1 = [1, 2, 3];
$arr2 = [...$arr1]; //[1, 2, 3]
$arr3 = [0, ...$arr1]; //[0, 1, 2, 3]
$arr4 = array(...$arr1, ...$arr2, 111); //[1, 2, 3, 1, 2, 3, 111]
$arr5 = [...$arr1, ...$arr1]; //[1, 2, 3, 1, 2, 3]
function getArr() {
return ['a', 'b'];
}
$arr6 = [...getArr(), 'c']; //['a', 'b', 'c']
$arr7 = [...new ArrayIterator(['a', 'b', 'c'])]; //['a', 'b', 'c']
function arrGen() {
for($i = 11; $i < 15; $i++) {
yield $i;
}
}
$arr8 = [...arrGen()]; //[11, 12, 13, 14]
It works like in JavaScript ES6.
See more on https://wiki.php.net/rfc/spread_operator_for_array.
Warning! $array1 + $array2 overwrites keys, so my solution (for multidimensional arrays) is to use array_unique()
array_unique(array_merge($a, $b), SORT_REGULAR);
Notice:
5.2.10+ Changed the default value of
sort_flags
back to SORT_STRING.5.2.9 Default is SORT_REGULAR.
5.2.8- Default is SORT_STRING
It perfectly works. Hope it helps same.
To do this, you can loop through one and append to the other:
<?php
$test1 = array(
'11' => '11',
'22' => '22',
'33' => '33',
'44' => '44'
);
$test2 = array(
'44' => '44',
'55' => '55',
'66' => '66',
'77' => '77'
);
function combineWithKeys($array1, $array2)
{
foreach($array1 as $key=>$value) $array2[$key] = $value;
asort($array2);
return $array2;
}
print_r(combineWithKeys($test1, $test2));
?>
UPDATE: KingCrunch came up with the best solution: print_r($array1+$array2);
Source: Stackoverflow.com