how to do array concetinnation in php code example

Example 1: merge array php

<?php
$array1    = array("color" => "red", 2, 4);
$array2    = array("a", "b", "color" => "green", "shape" => "trapezoid", 4);
$resultado = array_merge($array1, $array2);
print_r($resultado);
?>

Example 2: php combine values of two arrays

$all_arrays = array_merge($array1, $array2, $array3, ...);