php生成csv乱码怎么办

header("Content-Type: application/force-download"); 
header("Content-type:text/csv;charset=gb2312"); 
header("Content-Disposition:filename=打开邮件导出".date("YmdHis").".csv"); 
echo "收件人邮箱,收件人姓名,发送时间\r";
 ob_end_flush();
 foreach($list as $rs) { 
echo $rs->toemail.",".$rs->name.",".date('Y-m-d H:i:s',$rs->addtime)."\r"; flush();
 }
 exit;

header("Content-Type: application/force-download");
header("Content-type:text/csv;charset=gb2312");
header("Content-Disposition:filename=打开邮件导出".date("YmdHis").".csv");
echo chr(0xEF).chr(0xBB).chr(0xBF);
echo "收件人邮箱,收件人姓名,发送时间\r";
ob_end_flush();
foreach($list as $rs)
{
   echo $rs->toemail.",".$rs->name.",".date('Y-m-d H:i:s',$rs->addtime)."\r";
   flush();
}
exit;