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如何调用类外的变量

本帖最后由 hicoo 于 2014-06-07 10:21:04 编辑 a.php页面是数据链接变量
$dbhost = "localhost";
$dbname = "ffff";
$dbuser = "cccc";
$dbpwd = "123456";
$dbprefix = "user";
$db_language = "gbk";

b.php页面类里面为各种数据库的操作函数
require_once("../data/a.php");
class mydatabase{

// 链接数据库
  function opendata($database){
  请问在此方法中,怎么把类外的变量都获取
 }


//查询一条记录
  function ReadOne($database){
self::opendata($database);
$rs = mysql_query("SELECT * from fcc where id=1");
$row = mysql_fetch_array($rs); 
self::closedata();
return $row["date"];
 }

}
------解决方案--------------------
// 链接数据库
  function opendata($database){
  include("../data/a.php");
 }

或者定义成常量

你在类定义外面 require_once("../data/a.php")
将导致数据库相关参数变成全局变量,可能会覆盖掉同名变量
也可以通过 $GLOBALS 数组轻易的观察到
------解决方案--------------------
你要多看基础哦
<br />require_once("../data/a.php");<br /><br />class mydatabase {<br /><br />    // 链接数据库<br />    function opendata($database) {<br />        //方法一<br />        global $dbhost , $dbname , $dbuser , $dbpwd , $dbprefix , $db_language;<br />        //方法二<br />        require_once("../data/a.php");<br />        //方法三<br />        //在a.php把变量全部定义成常量<br />        define('DB_HOST' , 'test');<br />        //调用的时候直接 使用DB_HOST<br />        echo DB_HOST;<br />         <br />    }<br /><br /><br />    //查询一条记录<br />    function ReadOne($database) {<br />        self::opendata($database);<br />        $rs = mysql_query("SELECT * from fcc where id=1");<br />        $row = mysql_fetch_array($rs);<br />        self::closedata();<br />        return $row["date"];<br />         <br />    }<br /><br />}<br />

------解决方案--------------------
建议a.php的那些变量写进一个同一个数组,也可改成function 然后return这个数组
命名污染 有时候挺恶心的
------解决方案--------------------
一般这些配置信息最好变成常量
------解决方案--------------------
引用:
非常感谢以上两位高手,然后我想把获取变量的代码放在构造函数可以吗,因为我在别的方法里也会用到有些变量,那不是又要引用一次,但是构造函数的多个变量如何返回(return)呢?
class mydatabase{
  private $myhost;
  private $myuser;
  private $mypwd;

  public function __construct(){
    require_once("../data/a.php");
$this->myhost=$dbhost;
$this->myuser=$dbuser;
$this->mypwd=$dbpwd;
return $this->myhost; 
  请问这里多个变量如何返回呢,测试如果没有return的话,别的方法获取不到
//echo $dbhost;
  }

function opendata($database){
    $this->__construct();
$linkid = mysql_connect($this->myhost, $this->myuser, $this->mypwd);
}

}

第一种方法,用常量,这样在任何地方都可以使用了
../data/a.php
<br /><?php<br />    define('MYHOST', 'localhost');<br />    define('MYUSER', 'cccc');<br />    define('MYPWD', '123456');<br />?><br />

<br /><?php<br />require_once("../data/a.php");<br /><br />class mydatabase{<br /><br />    private $myhost;<br />    private $myuser;<br />    private $mypwd;<br /><br />    public function __construct(){<br />        $this->myhost = MYHOST;<br />        $this->myuser = MYUSER;<br />        $this->mypwd = MYPWD;<br />    }<br /><br />    function opendata($database){<br />        $linkid = mysql_connect($this->myhost, $this->myuser, $this->mypwd);<br />    }<br /><br />}<br />?><br />


第二种,用config数组
../data/a.php
<br /><?php<br />return array(<br />    'myhost' => 'localhost',<br />    'myuser' => 'cccc',<br />    'mypwd' => '123456'<br />);<br />

<br><?php <br />class mydatabase{<div class="clear">
                 
              
              
        
            </div>
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