Array_merge function attribute in PHP (where one parameter is null)

Two arrays that are read from the database need to be merged, with the Array_merge function in PHP, and the final result is always null, and by dump, it is discovered that one of the arrays is null. The demo is as follows:

<?php

$arr 1 =null;

$arr 2 = Array (' Tom ', ' linken ');

$arr 3 = Array_merge ($arr 1, $arr 2);

Var_dump ($arr 3);

The result of the run is null.

The solution is to force the type conversion of two parameters at the time of merge.

As follows:

<?php

$arr 1 =null;

$arr 2 = Array (' Tom ', ' linken ');

$arr 3 =array_merge ((array)$arr 1,(array)$arr 2);

Var_dump ($arr 3);

The result of the operation is:

Array (2) {[0]=> string (3) "Tom" [1]=> string (6) "Linken"}

The problem is resolved so that you do not have to determine whether $ARR1 and $ARR2 are null in your code.

Array_merge function attribute in PHP (where one parameter is null)