實例方法
random
randomElement()
返回集合的隨機元素。
聲明
func randomElement() -> Self.Element?
返回值
集合中的隨機元素。如果集合為空,則該方法返回 nil
。
詳述
調用 randomElement()
從數組或另一個集合中選擇一個隨機元素。此示例從數組中隨機選擇一個名稱:
let names = ["Zoey", "Chloe", "Amani", "Amaia"]
let randomName = names.randomElement()!
// randomName == "Amani"
該方法相當於調用randomElement(using:)
,傳入係統默認的隨機生成器。
可用版本
iOS 8.0+, iPadOS 8.0+, macOS 10.10+, Mac Catalyst 13.0+, tvOS 9.0+, watchOS 2.0+
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注:本文由純淨天空篩選整理自apple.com大神的英文原創作品 CollectionDifference randomElement()。非經特殊聲明,原始代碼版權歸原作者所有,本譯文未經允許或授權,請勿轉載或複製。