摘要：<?php class Db{ //数据库的配置信息 private static $dbConnect; private $dbConfig = array( 'host' => '12
<?php
class Db{
//数据库的配置信息
private static $dbConnect;
private $dbConfig = array(
'host' => '127.0.0.1',
'user' => 'root',
'password' => 'root',
'database' => 'php',
);
//将构造方法私有化:禁止从外部实例化类
private function __construct() {}
//将克隆方法私有化:禁止从外部克隆该类的实例
private function __clone() {}
//创建内部属性$instance,用来保存当前类实例
protected static $instance = null;
//创建外部接口,用来返回当前类的唯一实例
public static function getInstance()
{
if (is_null(static::$instance)) {
static::$instance = new static();
}
return static::$instance;
}
public function connect(){
self::$dbConnect = mysql_connect($this->dbConfig['host'],
$this->dbConfig['user'],$this->dbConfig['password']);
//验证数据库连接
if(!self::$dbConnect){
throw new Exception("mysql connect error".mysql_error());
}
//设置字符集
mysql_query("SET NAMES UTF8");
//连接数据库
mysql_SELECT_db($this->dbConfig['database'],self::$dbConnect);
return self::$dbConnect;
}
}
//从类的外部实例化当前类
$Db_connect= Db::getInstance();
?>
批改老师：天蓬老师批改时间：2019-03-21 13:06:03
老师总结：throw new Exception("mysql connect error".mysql_error());
这个习惯比较好, 不过, 上线后, 记得把它注释掉
