php join函数应用

$key = array();
$val = array();
foreach ($_POST as $k=>$v)
{
$key[] = `.strip_tags(mysql_real_escape_string(trim($k))).`;
$val[] = "".strip_tags(mysql_real_escape_string(trim($v)))."";
}

$keys = join(",",$key);
$vals = join(",",$val);