PHP实现基于面向对象的mysqli扩展库增删改查操作工具类

<?php //数据库操作类 class DBUtil{  private $host="localhost";  private $username="root";  private $password="123456";  private $dbname="student";  private $conn;  public function DBUtil(){   $this->conn=new mysqli($this->host, $this->username, $this->password,$this->dbname) or die($this->conn->connect_error);  } //查询  public function query($sql){   $all= $this->conn->query($sql);   return $all;  } //插入,修改，删除  public function otherOperate($sql){   if($this->conn->query($sql)){    if($this->conn->affected_rows>0){      return "OK";    }else{      return "ERROOR";    }   }  }  public function close(){   $this->conn->close();  } }?>

<?php require_once "MySQLUtil.php";  /*$sql="select * from m_student";  $util=new DBUtil();  $result=$util->query($sql);  while($row=$result->fetch_assoc()){   echo "$row[stuName]"."</br>";  }  $result->free();  $util->close();*/  $sql="update m_student set stuName='杨幂' where id=3";  $util=new DBUtil();  $result=$util->otherOperate($sql);  echo $result;  $util->close();?