我有一个包含三个方法的类。所有这些方法都需要数据库,然后我想创建一个用于连接数据库的系统。像这样的东西:
Class myclass
{
private $db;
public function __construct() {
$db = new PDO("mysql:host = hostname; dbname = database",username, password);
}
function one() {/* it needs to database and I will use it like this: */
$this->$db->prepare("select ...");
}
function two() {/* also it needs to database */}
function three() {/* also it needs to database */}
}
现在,我想(首先)知道我做的是标准方法?和(第二)如何检查[如果连接断开(换句话说,连接不存在)然后连接]?
要访问类属性,必须使用->
语法:
Class myclass
{
private $db;
public function __construct() {
$this->db = new PDO("mysql:host = hostname; dbname = database",username, password);
}
function one() {/* it needs to database and I will use it like this: */
$this->db->prepare("select ...");
}
function two() {/* also it needs to database */}
function three() {/* also it needs to database */}
}
如果要检测错误,请使用以下命令启用错误信号发送功能
$this->db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
并使用try/catch
使用该数据库的代码:
function one() {
try {
$this->db->prepare(...);
} catch (PDOException $e) {
// handle error
}
}
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我来说两句