将变量值中的"\n"回车全部转换成HTML的
  <br />。
  等同于PHP的
   nl2br()函数。
  
Example 5.14. nl2br
<?php
$smarty->assign('articleTitle',
                "Sun or rain expected\ntoday, dark tonight"
                );
?>
   
模板:
{$articleTitle|nl2br}
   
输出:
Sun or rain expected<br />today, dark tonight
   See also
   word_wrap,
   count_paragraphs
   and
   count_sentences.