function setOptions($opt = array())
{
if (!isset($opt['merchant']) || !isset($opt['secretkey'])) {
die("No params");
}
self::$merchant = $opt['merchant'];
self::$key = $opt['secretkey'];
unset($opt['merchant'], $opt['secretkey']);
if (count($opt) === 0) {
return $this;
}
foreach ($opt as $k => $v) {
$this->{$k} = $v;
}
return $this;
}