php禁用缓存代码

php中header("cache-control:no-cache,must-revalidate")...
ader("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . "GMT");
header("Cache-Control: no-cache, must-revalidate");
header("Pragma: no-cache");
上面组合是禁用缓存

header("Content-Language: charset=zh-cn");
说明字符集是简体中文

header("Content-type: text/html; charset=GB2312");
说明本页面是HTML内容，字符集是简体中文