edit

youzan/src/Card.php

@@ -21,6 +21,12 @@ class Card
 		return $len;
 	}
 
+	public function len($id = false)
+	{
+		$id = Dever::input('id', $id);
+		return Dever::lock($this->lock . '_' . $id);
+	}
+
 	public function total()
 	{
 		$info = Dever::db('youzan/card')->state();