实例方法
random
randomElement()
返回集合的随机元素。
声明
func randomElement() -> Self.Element?
返回值
集合中的随机元素。如果集合为空,则该方法返回 nil
。
详述
调用 randomElement()
从数组或另一个集合中选择一个随机元素。此示例从数组中随机选择一个名称:
let names = ["Zoey", "Chloe", "Amani", "Amaia"]
let randomName = names.randomElement()!
// randomName == "Amani"
该方法相当于调用randomElement(using:)
,传入系统默认的随机生成器。
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:本文由纯净天空筛选整理自apple.com大神的英文原创作品 AnyBidirectionalCollection randomElement()。非经特殊声明,原始代码版权归原作者所有,本译文未经允许或授权,请勿转载或复制。