实例方法
map(_:)
返回一个数组,其中包含将给定闭包映射到序列元素的结果。
声明
func map<T>(_ transform: (Self.Element) throws -> T) rethrows -> [T]
返回值
包含此序列的转换元素的数组。
参数
transform
映射闭包。
transform
接受此序列的元素作为其参数,并返回相同或不同类型的转换值。
详述
在此示例中,首先使用map
将数组中的名称转换为小写字符串,然后对其字符进行计数。
let cast = ["Vivien", "Marlon", "Kim", "Karl"]
let lowercaseNames = cast.map { $0.lowercased() }
// 'lowercaseNames' == ["vivien", "marlon", "kim", "karl"]
let letterCounts = cast.map { $0.count }
// 'letterCounts' == [6, 6, 3, 4]
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 UnsafeMutableBufferPointer map(_:)。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。