如何在 Swift 中获取数组的最后一个元素？

我能做到:

var a = [1,5,7,9,22]
a.count               // 5
a[a.count - 1]        // 22
a[a.endIndex - 1]     // 22

但肯定还有更好的办法吧？

swift

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最佳答案

Update: Swift 2.0 now includes first:T? and last:T? properties built-in.

When you need to you can make the built-in Swift API's prettier by providing your own extensions, e.g:

extension Array {
var last: T {
return self[self.endIndex - 1]
}
}

This lets you now access the last element on any array with:

[1,5,7,9,22].last

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As of beta5 there is now a first and last property

In addition to Array acquiring first and last, the lazy collections also implement first (and last if they can index bidirectionally), as well as isEmpty.

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You can also get and remove last element from array
removeLast()

Example:

var array = [1, 2, 3]
let removed = array.removeLast()
// array is [1, 2]
// removed is 3

Taken from Apple docs (this source expired but you can find examples in this documentation page)

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You can fetch the last element of an Array by using the last property.

Code:

let lastElement = yourArray.last

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edit for swift 2.2

extension Array {
var last: Element {
return self[self.endIndex - 1]
}
}

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swift 5:

if let last = a.last {
print(last)
}