I can think of two possible reasons that this is happening.
1.
You are using a single quoted string:
$array = preg_split("/\n|,/", 'foo,bar\nbaz');
print_r($array);
Array
(
[0] => foo
[1] => bar\nbaz
)
If so, use double quotes "
instead ...
$array = preg_split("/\n|,/", "foo,bar\nbaz");
print_r($array);
Array
(
[0] => foo
[1] => bar
[2] => baz
)
2.
You have multiple newline sequences and I would recommend using \R
if so. This matches any Unicode newline sequence that is in the ASCII
range.
$array = preg_split('/\R|,/', "foo,bar\nbaz\r\nquz");
print_r($array);
Array
(
[0] => foo
[1] => bar
[2] => baz
[3] => quz
)