Swift:从元组中获取一个元素 [英] Swift: Get an element from a tuple

问题描述

如果我有这样的元组

var answer: (number: Int, good: Bool)

我如何获得其中一个元素?

How do I get one of the elements?

这不起作用:

answer["number"]

我在 Swift 之后建模这个问题:从元组数组中获取元素数组，但我的问题更基本一些.我确实在文档中找到了答案所以我在下面以问答格式添加我的答案，以便将来更快地搜索.

I am modeling this question after Swift: Get an array of element from an array of tuples, but my question was a little more basic. I did find the answer buried in the documentation so I am adding my answer below in Q&A format for faster searching in the future.

推荐答案

根据 文档(向下滚动到元组)，有三种方法可以做到.

According to the documentation (scroll down to Tuples), there are three ways to do it.

给定

var answer: (number: Int, good: Bool) = (100, true)

方法一

将元素变量名称放在一个元组中.

Put the element variable name within a tuple.

let (firstElement, _) = answer
let (_, secondElement) = answer

或

let (firstElement, secondElement) = answer

方法二

使用索引.

let firstElement = answer.0
let secondElement = answer.1

方法三

使用名称.当然，这仅适用于在元组声明中命名元素的情况.

Use the names. This only works, of course, if the elements were named in the Tuple declaration.

let firstElement = answer.number
let secondElement = answer.good

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