Swift:可选数组的快捷展开

Question

假设我们定义了一个可选数组:

var arrayOfOptionals: [String?] = ["Seems", "like", "an", nil, "of", "optionals"]

我可以用一种简短的方式强制解包:var arrayForCrash = arrayOfOptionals.map { $0! }

但这会使应用程序崩溃，是否有任何其他捷径​​(无需显式解包)如何解包可选数组？

Answer 1

此解决方案将为您提供一个新数组，其中所有值都已展开并过滤掉所有 nil。

swift 4.1:

let arrayOfOptionals: [String?] = ["Seems", "like", "an", nil, "of", "optionals"]
let arrayWithNoOptionals = arrayOfOptionals.compactMap { $0 }

swift 2.0:

let arrayOfOptionals: [String?] = ["Seems", "like", "an", nil, "of", "optionals"]
let arrayWithNoOptionals = arrayOfOptionals.flatMap { $0 }

swift 1.0:

let arrayOfOptionals: [String?] = ["Seems", "like", "an", nil, "of", "optionals"]
let arrayWithNoOptionals = arrayOfOptionals.filter { $0 != nil }.map { $0! }