ios – 如何将带有枚举键的Swift词典转换为NSDictionary？

我无法将 Swift字典转换为NSDictionary.我使用Swift枚举作为我的字典的关键：

enum StringEnum : String {
    case Lemon = "lemon"
    case Orange = "orange"
}

var swiftDictionary = [StringEnum: AnyObject]()
swiftDictionarY[.Lemon] = "String value"
swiftDictionarY[.orange] = 123

当我尝试使用as关键字将其转换为NSDictionary时：

let objcDictionary: NSDictionary = swiftDictionary as NSDictionary

我收到编译器错误：

'[StringEnum : AnyObject]' is not convertible to 'NSDictionary'

可以转换这些类型的字典,还是需要循环Swift字典并手动创建NSDictionary？

//change the type of your Dict to [String: AnyObject]()
var swiftDictionary = [String: AnyObject]()

//you can store rawValue as a key
swiftDictionarY[StringEnum.Lemon.rawValue] = "String value"
swiftDictionarY[StringEnum.Orange.rawValue] = 123

let objcDictionary = swiftDictionary as NSDictionary  //["lemon": "String value","orange": 123]