将数字转换为相应单词的最佳方法是什么？

Question

let numberDict = [ 1: "one", 2: "two", 3: "three", 4: "four", 5: "five"]
print(numberDict[5] ?? "don't know")

将数字转换为相应字词的最佳方法是什么？

Answer 1

Foundation库有一个内置的NumberFormatter类，可以拼出数字：

let number = 1
let formatter = NumberFormatter()
formatter.numberStyle = .spellOut
let numberString = formatter.string(from: number)

在上面的例子中，numberString是＆＃34;一个＆＃34; （可选的）。请注意，NumberFormatter不能识别区域设置。

Answer 2

如果你想发疯，你可以使用枚举（但在某种程度上，它会回到switch）：

enum Number: Int, CustomStringConvertible {
    case one = 1
    case two = 2
    case three = 3
    case four = 4
    case five = 5

    var description: String {
        switch self {
        case .one: return "one"
        case .two: return "two"
        case .three: return "three"
        case .four: return "four"
        case .five: return "five"
        }
    }
}

let number = 3
let enumedNumber: Number? = Number(rawValue: number)

print(enumedNumber ?? "Don't know")

Answer 3

如果您需要自己定义名称，最短的解决方案是

let array = ["one", "two", "three", "four", "five"]
let number = 1
print(number > 0 && number <= array.count ? array[number - 1] : "unknown")

如果你喜欢疯狂的方法，你可以使用

print(NSLocalizedString(number, comment: ""))

包含

的Localizable.strings文件

"1" = "one";
"2" = "two";
"3" = "three";
"4" = "four";
"5" = "five";