how to concat two array elements of same array in php code example

Example 1: php array merge for associative arrays

<?php

$array1 = array('key1' => 'test1', 'key2' => 'test2');
$array2 = array('key3' => 'test3', 'key4' => 'test4');

$resultArray = array_merge($array1, $array2);

// If you have numeric or numeric like keys, array_merge will 
// reset the keys to 0 and start numbering from there

$resultArray = $array1 + $array2;

// Using the addition operator will allow you to preserve your keys,
// however any duplicate keys will be ignored.

Example 2: merge two arrays one as key to another php

// two arrays one become keys and second becomes values
array_combine ( array $keys , array $values );