怎么处理mcrypt_encrypt()加密中文后，就显示为乱码了，还原后也是

header("Content-Type:text/html; charset=utf-8");



$str="床前明月光,疑是地上霜"; //被加密的内容

$key="key:111"; //密匙

$cipher=MCRYPT_DES;  //加密算法类型

$mode=MCRYPT_MODE_ECB;  //加密算法模式

$iv=mcrypt_create_iv(mcrypt_get_iv_size($cipher, $mode),MCRYPT_RAND); //初始化向量

echo "加密前".$str."
";

//加密

$str_encrypt=mcrypt_encrypt($cipher,$key,$str,$mode,$iv);

echo "加密后".$str_encrypt."
";

//还原

$str_decrypt=mcrypt_encrypt($cipher,$key,$str_encrypt,$mode,$iv);

echo "还原".$str_decrypt."
";



?>