1、使用mysqli扩展库 预处理技术 mysqli stmt 向数据库添加3个用户   复制代码 代码如下:     <?php   //mysqli扩展库 预处理技术 mysqli stmt 向数据库添加3个用户 //1、创建mysqli对象 $mysqli = new MySQLi("localhost","root","root","test"); if($mysqli->connect_error){ die($mysqli->conncet_error); } //2、创建预编译对象 $sql="insert into user1(name,password,email,age) values(?,?,?,?)"; $mysqli_stmt=$mysqli->prepare($sql);   //绑定参数 $name="小芳"; $password="123456"; $email="[email protected]"; $age=18;   //参数绑定->给？号赋值 这里类型和顺序要一致 $mysqli_stmt->bind_param("sssi",$name,$password,$email,$age);   //执行 $b=$mysqli_stmt->execute();   //继续添加   $name="小杨"; $password="123456"; $email="[email protected]"; $age=18;   //参数绑定->给？号赋值 这里类型和顺序要一致 $mysqli_stmt->bind_param("sssi",$name,$password,$email,$age);   //执行 $b=$mysqli_stmt->execute();   //继续添加   $name="小G"; $password="123456"; $email="[email protected]"; $age=18;   //参数绑定->给？号赋值 这里类型和顺序要一致 $mysqli_stmt->bind_param("sssi",$name,$password,$email,$age);   //执行 $b=$mysqli_stmt->execute();   if(!$b){ echo "操作失败".$mysqli_stmt->error; }else{ echo "操作成功"; } //关闭预编译 $mysqli_stmt->close(); $mysqli->close(); ?>     2、使用预处理查询id>5的用户id name email 复制代码 代码如下:     <?php   //使用预处理查询id>5的用户id name email $mysqli=new MySQLi("localhost","root","root","test"); if($mysqli->connect_error){ die($mysqli->connect_error); }   //创建预编译对象 $sql="select id,name,email from user1 where id>?"; $mysqli_stmt=$mysqli->prepare($sql);   $id=5; //绑定参数 $mysqli_stmt->bind_param("i",$id); //绑定结果集 $mysqli_stmt->bind_result($id,$name,$email); //执行 $mysqli_stmt->execute();   //取出绑定的值 while($mysqli_stmt->fetch()){ echo "<br/>$id--$name--$email"; }   //关闭资源 //释放结果 $mysqli_stmt->free_result(); //关闭与编译语句 $mysqli_stmt->close(); //关闭连接 $mysqli->close();   ?>