困惑斯威夫特数组声明 [英] Confused about Swift Array Declarations

问题描述

有以下有何区别？

1. VAR array1_OfStrings = [字符串]（）

VAR array2_OfStrings：[字符串] = []

在测试游乐场显示，1和2是相同的，但3的行为不同。
有人可以解释我的区别吗？而且这将是申报字符串？

Testing in Playground shows that 1 and 2 are the same but 3 behaves differently. Can someone explain me the difference please? And also what will be the preferred way to declare an empty array of String?

推荐答案

首先两者具有同样的效果。

First two have the same effect.

1. 声明一个变量 array1_OfStrings ，让它选择类型本身。当它看到 [字符串]（），它巧妙地知道这是字符串类型的数组。

1. declare a variable array1_OfStrings, let it choose the type itself. When it sees [String](), it smartly knows that's type array of string.

您设置变量 array2_OfStrings 作为字符串类型的数组，那你说这由 []

You set the variable array2_OfStrings as type array of string, then you say it's empty by []

这是<强>不同的因为你只是告诉你想要 array3_OfStrings 是字符串类型的数组，但没有给它一个初始值

This is different because you just tell you want array3_OfStrings to be type array of string, but not given it an initial value.

我认为第一个被推荐为<一个href=\"https://developer.apple.com/library/$p$prelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/CollectionTypes.html#//apple_ref/doc/uid/TP40014097-CH8-ID107\"相对=nofollow>雨燕编程语言使用它更频繁。

I think the first one is recommended as The Swift Programming Language uses it more often.

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