简单的数据库链式操作的例子

<?php

/* 

@author Dishy 
数据库封装 
*/ 
class mysqldb{

private $host;private $username;private $password;private $dbname;private $sql;private $select = true;private $result;private $array;public function __construct($host,$username,$password,$dbname){    $this->host = $host;    $this->username = $username;    $this->password = $password;    $this->dbname = $dbname;    $this->dbconnect();}/*    数据库连接*/private function dbconnect(){    mysql_connect($this->host,$this->username,$this->password);    mysql_select_db($this->dbname);}/**执行sql语句***/public function query($sql){        $this->sql = $sql;        $this->result = mysql_query($this->sql);        return $this;}/***$select = false时输出sql语句*/public function select($select= true){    $this->select = $select;    if($this->select){        return $this->array =  $this->result();    }else{        return $this->sql;    }}/***结果集*/private function result(){    $array = mysql_fetch_array($this->result);    return $array;}

}

?> 
使用方法 include “./Api/datebase.php”; 
define('DB_HOST_NAME','localhost'); 
define('DB_HOST_USERNAME','root'); 
define('DB_HOST_PASSWORD','root'); 
define('DB_HOST_DB','jciot'); 
$Jciot_db = new mysqldb(DB_HOST_NAME,DB_HOST_USERNAME,DB_HOST_PASSWORD,DB_HOST_DB); 
$a = $Jciot_db->query('select * from jciot_member')->select(); 
var_dump($a);

?>`