PHP: Array merge issue A - Z != a - z

Question

What's wrong with this array merge?

$array_az = range('a', 'z');
$array_AZ = range('A', 'Z');
$array_09 = range(0, 9);
array_merge($array_az, $array_AZ, $array_09);
print_r($array_az); // a, b, c ... z, 0, 1 ...

But I want something like: // a, b, c, ... z, A, B, C, ... Z, 0, 1 ...

How could I get this output? Thank you.

Answer 1

array_merge returns the merged result, which means you need to store it.

$merged_array = array_merge($array_az, $array_AZ, $array_09);
print_r($merged_array);

Answer 2

array_merge returns the resulting array. You should be saving the result

$merged = array_merge($array_az, $array_AZ, $array_09);

Answer 3

array_merge returns a new array and does not act on an array by reference. Try the following:

$array_az = array_merge($array_az, $array_AZ, $array_09);

$array_az will now contain your desired result.