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);

?>`