Php explode string by newline : You can use PHP_EOL to explode string at line break.
Php explode string by newline break
$array = explode(PHP_EOL, $string);
Which will break the string at the break line.
Php explode array at line break Example
$string = " str1
str2
str3";
$array = explode(PHP_EOL, $string);
print_r($array);
array('0'=>'str1','1'=>'str2','2'=>'str3');