PHP str_replace

* str_replace
$content=str_replace($content, "''", "'");
$content=str_replace($content, " ", chr(32));
$content=str_replace($content, "<", "<");
$content=str_replace($content, ">", ">");
$content=str_replace($content, "&", "&");
$content=str_replace($content, chr(13), "<br>");

* today
$today=date("Y-m-d h:i");