这是我第一次使用PDO进行测试。但是出现了一个奇怪的错误,经过谷歌搜索,发现这个错误很奇怪。
以下是我的数据库测试类:
class db extends PDO
{
# Our instance.
private static $db = NULL;
# Calling the connector.
public static function connect()
{
if (self::$db === NULL)
{
$class = __CLASS__;
self::$db = new $class();
}
return self::$db;
}
# Connector.
public function __construct()
{
$dns = 'mysql:dbname='.reg::get('db-name').';host='.reg::get('db-host');
self::$db = new PDO($dns, reg::get('db-username'), reg::get('db-password'));
reg::delete('db-password');
}
# Quick reporting
public function reportError($array)
{
if ($this->db != NULL) { echo 'Myself getting horny'; } // Just for testing, i'm not getting horny because of a mysql database connection!
}
}
那么执行以下代码:
$db = new db();
$row = $db->prepare('SELECT * FROM test WHERE id = :id')->execute(array('id' => 1));
echo $row['value'];
它向我显示以下错误:
Warning: PDO::prepare() [pdo.prepare]: SQLSTATE[00000]: No error: PDO constructor was not called in myfile.php on line 39
将第39行视为
$row = $db->prepare('SELECT * FROM test WHERE id = :id')->execute(array('id' => 1));
$db
是否为空而不是self::$db
?为什么要执行self::$db = new db();
。 - Alix Axel