Swift:可选数组的快捷方式解包 [英] Swift: shortcut unwrapping of array of optionals

问题描述

假设我们定义了一个可选的数组:

Assume we have an array of optionals defined:

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

我可以用简短的方式强制解开它:var arrayForCrash = arrayOfOptionals.map { $0!}

I can force unwrap it in a short way: var arrayForCrash = arrayOfOptionals.map { $0! }

但这会使应用程序崩溃，有没有其他简短的方法(无需明确解包)如何解包可选数组?

But that will make app to crash, is there any other short way(without explicitly unwrapping) how I can unwrap an array of optional?

推荐答案

此解决方案将为您提供一个新数组，其中所有值都已解开并过滤掉所有 nil.

This solution will get you a new array with all values unwrapped and all nil's filtered away.

斯威夫特 4.1:

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

斯威夫特 2.0:

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

斯威夫特 1.0:

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

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