PHP msqli ->query() 乱码解决

$mysqli = new mysqli(‘localhost’,’root’,’password’,’dbname’);//mysqli链接数据库的写法

//$mysqli->query(“SET NAMES utf8”);//写法一

mysqliquery(db,”SET NAMES utf8”);//写法二

<?php        $efly_id= $_REQUEST["efly_id"];        echo $efly_id;        $mysql_server="localhost";        $mysql_user="root";        $mysql_password="123456";        $mysql_database="efly_service_database";        echo $mysql_database;        $conn=new mysqli($msql_server,$mysql_user,$mysql_password,$mysql_database);        if(!$conn->connect_error){        echo "数据库连接成功";        $conn->query("set names utf8");        $select="select username from efly_service_user where efly_id= 'a'";        $result=  $conn->query($select);         while($row=mysqli_fetch_assoc($result)){        echo "<p>".$row["username"]."</p>";}//        echo "<p> <strong>$username</strong></p>";        $conn->close();        }else{        echo "数据库连接失败";        }?>