laravel append array to array

1$arr = ["1", "2"];
2array_push($arr, "3");

1$fruits = ["apple", "banana"];
2// array_push() function inserts one or more elements to the end of an array
3array_push($fruits, "orange");
4
5// If you use array_push() to add one element to the array, it's better to use
6// $fruits[] = because in that way there is no overhead of calling a function.
7$fruits[] = "orange";
8
9// output: Array ( [0] => apple [1] => banana [2] => orange )

1$array = array('foo' => 'bar');
2
3$array = array_add($array, 'key', 'value');