Swift：快捷方式展开可选数组

小编典典

Swift：快捷方式展开可选数组

swift

假设我们定义了一个可选数组：

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

我可以在短时间内强行打开包装： var arrayForCrash = arrayOfOptionals.map { $0! }

但这会使应用程序崩溃，是否还有其他短途方法（无需显式展开）如何展开可选数组？

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2020-07-07

共1个答案

小编典典

此解决方案将为您提供一个新数组，其中所有值均已解包且所有nil均被滤除。

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! }

2020-07-07