mysqli面向过程练手

代码:
//1.得到mysqli连接
       header("Content-type: text/html;charset=utf-8");
       $mysqli=mysqli_connect("localhost","root","root","test");
       if(!$mysqli){
              die("连接失败".mysqli_connnect_error($mysqli));
       }
       //2.向数据库发送sql语句(ddl,dml dql ...)
       $sql="select * from user1";
       $res=mysqli_query($mysqli,$sql);
       //var_dump($res);
       //3.处理得到的结果
       //循环取出$res中的数据mysqli_fetch_row mysql_fetch_row
       while($row=mysqli_fetch_row($res)){
              
              foreach($row as $key=>$val){
                     echo "--$val";
              }
              echo "<br/>";
       }
       //4.关闭资源
       mysqli_free_result($res);
       mysqli_close($mysqli);