javascript - why CRLF transformed to LF when they are assigned to using php -

javascript - why CRLF transformed to LF when they are assigned to <input> using php -

(1)a form include textarea,type text line break it.like :

a b

then submit form , store text database.the length of contents 4.i can output ascii codes,using ord() function.they 97(a), 13(cr), 10(lf), 98(b).

(2)get contents , assign them template using smarty.like:

//$string database. $smarty->assign('str', $string);

using input element store contents in html template.

<input id="test" type="hidden" value="{$str}">

(3)get length of input value

document.getelementbyid("test").value.length; //the result 3

while using

{$str|@strlen} //the result 4

if submit form , ascii code of cotents,they 97(a), 10(lf), 98(b). character 13(cr) lost.

i googled lot didn't find reason. explanation? lot in advance.

i found :

https://bugzilla.mozilla.org/show_bug.cgi?id=188015

someone replied in comment 28 , official docs transferred to:

http://www.w3.org/tr/html5/syntax.html#preprocessing-the-input-stream

"cr" (u+000d) characters , "lf" (u+000a) characters treated specially. cr characters must converted lf characters, , lf characters follow cr character must ignored.

hope help.

what happens html get's rendered (i've escaped cr character:)

<input id="test" type="hidden" value="a\13 b">

and browser trims whitespace, deleting cr character.

what can render urlencode($str) instead of plain $str variable. way browser won't mess command characters. you'll have urldecode on other side, though.

javascript php html dom