將AnyObject保存到NSUserdefaults

Question

我目前正在研究Swift應用程序，它通過Mobile Buy SDK與Shopify API交互。我在將購物車儲存到設備時遇到問題。其他一切工作正常，但是當我使用下面的代碼到購物車保存到設備：

func saveCart() { 
    NSUserDefaults.standardUserDefaults().setObject(cart, forKey: "cart") 
    println("cart saved") 
    } 

我收到以下錯誤：

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Attempt to insert non-property list object <BUYCart: 0x7fb5e30512f0> for key cart' 

Answer 1

從NSUserDefaults類參考：

The NSUserDefaults class provides convenience methods for accessing common types such as floats, doubles, integers, Booleans, and URLs. A default object must be a property list, that is, an instance of (or for collections a combination of instances of): NSData , NSString , NSNumber , NSDate , NSArray , or NSDictionary . If you want to store any other type of object, you should typically archive it to create an instance of NSData . For more details, see Preferences and Settings Programming Guide.

希望這有助於！