嘿，伙计们，我肯定又做错了，但我正在尝试实例化一个PDO数据库类中的处理程序AdminSession中文件class.Database.php中的数据库从class.admin.php，我的依赖性注射有点奇怪，但事实并非如此允许我正确使用PDO的方法；比如fetch（）、prepare（）等等。
class.database.php文件
class Database
{
public $db; // handle of the db connection
private static $dsn="mysql:host=server2.com;dbname=database";
private static $user="user";
private static $pass="pass";
private static $instance;
public function __construct ()
{
$this->db = new PDO(self::$dsn,self::$user,self::$pass,$self::$opts);
$this->db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$this->db->setAttribute(PDO::MYSQL_ATTR_INIT_COMMAND, "SET NAMES 'utf8'");
switch($_SERVER['ENVIRONMENT']) {
case 'staging':
self::$dsn="mysql:host=server1.com;dbname=database";
self::$user="user";
self::$pass="pass";
break;
default:
self::$dsn="mysql:host=server2.com;dbname=database";
self::$user="user";
self::$pass="pass";
}
}
public static function getInstance()
{
if(!isset(self::$instance))
{
$object= __CLASS__;
self::$instance=new $object;
}
return self::$instance;
}
}
这是我的类admin.php的最顶层，还有一个抛出错误的方法。现在错误我得到
PHP致命错误：调用未定义的方法行230
如果我使用$this->db-prepare($sql)
或
PHP致命错误：调用非对象行230上的成员函数prepare（）
如果我使用$db-prepare($sql)
require('library/class.database.php');
class AdminSession {
static $abs_path;
public function __construct(Database $db) {
session_start();
self::$abs_path = dirname(dirname(__FILE__));
if($_SERVER['REQUEST_METHOD'] == 'POST') {
$this->post = $_POST; // filter_input_array(INPUT_POST, FILTER_SANITIZE_STRING);
if(get_magic_quotes_gpc ()) {
//get rid of magic quotes and slashes if present
array_walk_recursive($this->post, array($this, 'stripslash_gpc'));
}
}
$this->get = $_GET; // filter_input_array(INPUT_GET, FILTER_SANITIZE_STRING);
array_walk_recursive($this->get, array($this, 'urldecode'));
}
// other methods
private function checkDB($username, $password) {
$sql = "SELECT * FROM users WHERE username=:username";
try {
$db = Database::getInstance();
$stmt = $db->prepare($sql);
$stmt->bindParam("username", $username);
$stmt->execute();
$user = $stmt->fetchAll(PDO::FETCH_OBJ);
$db = null;
if($user) {
//general return
if(is_object($user[0]) && md5($user[0]->password) == $password) {
return true;
} else {
return false;
}
} else {
return false;
}
} catch(PDOException $e) {
echo '{"error":{"text":'. $e->getMessage() .'}}';
}
}
}
您不能将逻辑放入类定义中。相反，在构造函数中确定这些变量的值。开关将在方法中起作用，但在定义成员时不起作用。
编辑：我真的觉得错过这个很傻。连接是在switch语句之前建立的。我不知道它能不能解决第二组问题。。。但它现在对最初的问题表现得很好。
class Database
{
public $db; // handle of the db connection
private static $opts = array(PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8');
private static $dsn="mysql:host=server2.com;dbname=database";
private static $user="user";
private static $pass="pass";
private static $instance;
public function __construct ()
{
switch($_SERVER['ENVIRONMENT']) {
case 'staging':
self::$dsn="mysql:host=server1.com;dbname=database";
self::$user="user";
self::$pass="pass";
break;
default:
self::$dsn="mysql:host=server2.com;dbname=database";
self::$user="user";
self::$pass="pass";
}
$this->db = new PDO(self::$dsn,self::$user,self::$pass,$self::$opts);
$this->db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
}
public static function getInstance()
{
if(!isset(self::$instance))
{
$object= __CLASS__;
self::$instance=new $object;
}
return self::$instance;
}
}