Test merge array php

test_array.php

<?php

$a = array('a' => array('b' => 1, 'c'=>1, 'd' => 1));
$b = array('a' => array('b' => 2, 'c'=>2, 'e' => 2));
$c1 = $a + $b;
$c2 = array_merge($a,$b);
$c3 = array_merge_recursive($a,$b);
$d2 = array_replace($a,$b);
$d3 = array_replace_recursive($a,$b);

echo 'a: '          . print_r($a,1);
echo 'b: '          . print_r($b,1);
echo '------------'.PHP_EOL;
echo 'a+b: '        . print_r($c1,1);
echo 'array_merge: '   . print_r($c2,1);
echo 'array_merge_recursive: ' . print_r($c3,1);
echo '------------'.PHP_EOL;
echo 'array_replace  : ' .print_r($d2,1);
echo 'array_replace_recursive: ' .print_r($d3,1);
echo '============'.PHP_EOL;

$a = array('b' => 1, 'c'=>1, 'd' => 1);
$b = array('b' => 2, 'c'=>2, 'e' => 2);
$c1 = $a + $b;
$c2 = array_merge($a,$b);
$c3 = array_merge_recursive($a,$b);
$d2 = array_replace($a,$b);
$d3 = array_replace_recursive($a,$b);

echo 'a: '          . print_r($a,1);
echo 'b: '          . print_r($b,1);
echo '------------'.PHP_EOL;
echo 'a+b: '        . print_r($c1,1);
echo 'array_merge: '   . print_r($c2,1);
echo 'array_merge_recursive: ' . print_r($c3,1);
echo '------------'.PHP_EOL;
echo 'array_replace  : ' .print_r($d2,1);
echo 'array_replace_recursive: ' .print_r($d3,1);
echo '============'.PHP_EOL;

Output:

a: Array
(
    [a] => Array
        (
            [b] => 1
            [c] => 1
            [d] => 1
        )

)
b: Array
(
    [a] => Array
        (
            [b] => 2
            [c] => 2
            [e] => 2
        )

)
------------
a+b: Array
(
    [a] => Array
        (
            [b] => 1
            [c] => 1
            [d] => 1
        )

)
array_merge: Array
(
    [a] => Array
        (
            [b] => 2
            [c] => 2
            [e] => 2
        )

)
array_merge_recursive: Array
(
    [a] => Array
        (
            [b] => Array
                (
                    [0] => 1
                    [1] => 2
                )

            [c] => Array
                (
                    [0] => 1
                    [1] => 2
                )

            [d] => 1
            [e] => 2
        )

)
------------
array_replace  : Array
(
    [a] => Array
        (
            [b] => 2
            [c] => 2
            [e] => 2
        )

)
array_replace_recursive: Array
(
    [a] => Array
        (
            [b] => 2
            [c] => 2
            [d] => 1
            [e] => 2
        )

)
============
a: Array
(
    [b] => 1
    [c] => 1
    [d] => 1
)
b: Array
(
    [b] => 2
    [c] => 2
    [e] => 2
)
------------
a+b: Array
(
    [b] => 1
    [c] => 1
    [d] => 1
    [e] => 2
)
array_merge: Array
(
    [b] => 2
    [c] => 2
    [d] => 1
    [e] => 2
)
array_merge_recursive: Array
(
    [b] => Array
        (
            [0] => 1
            [1] => 2
        )

    [c] => Array
        (
            [0] => 1
            [1] => 2
        )

    [d] => 1
    [e] => 2
)
------------
array_replace  : Array
(
    [b] => 2
    [c] => 2
    [d] => 1
    [e] => 2
)
array_replace_recursive: Array
(
    [b] => 2
    [c] => 2
    [d] => 1
    [e] => 2
)
============