Determine newline return method in PHP

Question

What would be the best way to detect newline return method in PHP. CR, LF or CR+LF

And if possible convert it to specified type.

Answer 1

define('NL_NIX', "\n");
define('NL_WIN', "\r\n");
define('NL_MAC', "\r");


function newline_type($string)
{
    if (strpos($string, NL_WIN) !== false) {
        return NL_WIN;
    } elseif(strpos($string, NL_MAC) !== false) {
        return NL_MAC;
    } elseif(strpos($string, NL_NIX) !== false) {
        return NL_NIX;
    }
}

Checks what kind of newline is in the string. 0 is returned when no newline is found.

To normalize/standardize all newlines use the following function:

function newline_convert($string, $newline)
{
    return str_replace(array(NL_WIN, NL_MAC, NL_NIX), $newline, $string);
}

Hope it helps!

Answer 2

This will test a string for a newline character (CR or LF):

function has_newline($string)
{
    return (strpos($string, "\r") !== false || strpos($string, "\n") !== false);
}

(\r means CR and \n means LF)

You can use the same thinking to convert them. For example, this function converts all CRs to LFs in a given string:

function replace_returns($string)
{
    return str_replace("\r", "\n", $string);
}

Answer 3

The constant PHP_EOL contains the platform specific newline character.

Answer 4

You can do a $string = nl2br($string) so that your line break is changed to

<br />. 

Then you can manipulate the string, e.g. split it up by the first occurance of

<br />

like this:

list($first, $second) = explode('<br />', $string, 2);