如何将换行符转换为\\ n

Question

I have a return string from a db.

The return string must be formatted in javascript.

<?php
    $db = "this is a line
           this is a new line";
?>

How would I convert the above to:

<?php $db = "this is a line \n this is a new line"; ?>

Javascript:

<script>
    var jdb = <?php echo $db; ?>
</script>

Answer 1

Try this (updated 2014-11-08):

<?php

   $db = "this is a line
          this is a new line
          ";

?>
<script type="text/javascript">
  var jdb = <?php echo json_encode($db) ?>;
</script>

Answer 2

$db = preg_replace("/\n/m", '\n', $db);

应该做的伎俩

Answer 3

要正确保留\\r和\\n换行符，您可以轻松使用strtr 。

$db = strtr( $db, array(  "\n" => "\\n",  "\r" => "\\r"  ));

Answer 4

我不明白这一点，但你可以（通过添加反斜杠来逃避换行）

$db = str_replace("\n","\\n",$db);

Answer 5

$db = str_replace("\r\n", "\\n", $db);

Answer 6

I am not sure if I understand correctly because \\n is a line break!?

But you may be need:

$db = str_replace("\r\n", "\n", $db);

Answer 7

You want to output that to javascript... hmm, so if you want to insert it into html you probably want something like this (the test ran):

<div id="test"></div>
<script type="text/javascript">
<?php
  $string = "123
  456"; // or $string = "123\n456";
  $string = str_replace(array("\r\n","\n"),"\\\\n",$string);
  echo "document.getElementById('test').innerHTML = '".htmlentities($string)."';";
?>
</script>

with output 123\\n 456 to the div through the js

If you simply want it as that in js, just remove two of the slashes so it's "\\n" in php and "\\n" in js.

Answer 8

You should look at nl2br(), which converts all new lines to HTML <br />. http://php.net/manual/en/function.nl2br.php