Array Operators
Array Operators
| Example | Name | Result |
|---|---|---|
| $a + $b | Union | Union of $a and $b. |
| $a == $b | Equality | TRUE if $a and $b have the same key/value pairs. |
| $a === $b | Identity | TRUE if $a and $b have the same key/value pairs in the same order and of the same types. |
| $a != $b | Inequality | TRUE if $a is not equal to $b. |
| $a <> $b | Inequality | TRUE if $a is not equal to $b. |
| $a !== $b | Non-identity | TRUE if $a is not identical to $b. |
The + operator returns the right-hand array appended to the left-hand array; for keys that exist in both arrays, the elements from the left-hand array will be used, and the matching elements from the right-hand array will be ignored.
<?php
$a = array("a" => "apple", "b" => "banana"
$b = array("a" => "pear", "b" => "strawberry", "c" => "cherry"
$c = $a + $b; // Union of $a and $b
echo "Union of \$a and \$b: \n";
var_dump($c
$c = $b + $a; // Union of $b and $a
echo "Union of \$b and \$a: \n";
var_dump($c
$a += $b; // Union of $a += $b is $a and $b
echo "Union of \$a += \$b: \n";
var_dump($a
?>
When executed, this script will print the following:
Union of $a and $b:
array(3) {
["a"]=>
string(5) "apple"
["b"]=>
string(6) "banana"
["c"]=>
string(6) "cherry"
}
Union of $b and $a:
array(3) {
["a"]=>
string(4) "pear"
["b"]=>
string(10) "strawberry"
["c"]=>
string(6) "cherry"
}
Union of $a += $b:
array(3) {
'a' =>
string(5) "apple"
'b' =>
string(6) "banana"
'c' =>
string(6) "cherry"
}
Elements of arrays are equal for the comparison if they have the same key and value.
Example #1 Comparing arrays
<?php
$a = array("apple", "banana"
$b = array(1 => "banana", "0" => "apple"
var_dump($a == $b // bool(true)
var_dump($a === $b // bool(false)
?>
See also the manual sections on the Array type and Array functions.
← String Operators
Type Operators →
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://secure.php.net/manual/en/language.operators.array.php
