Merge array items into string

Question

How do I merge all the array items into a single string?

Answer 1

$array1 = array(
    "one",
    "two",
)
$array2 = array(
    "three",
    "four",
)
$finalarr = array_merge($array1, $array2);
$finalarr = implode(",", $finalarr);

will produce this one,two,three,four