如何将带有枚举键的Swift词典转换为NSDictionary？

Question

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NSDictionary使用as关键字将其转换为a 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NSDictionary手动创建？

Answer 1

我想如果你的字典有枚举值,那么你就无法将其转换为NSDictionary另一种方法,那就是:

//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]

希望这会有所帮助.