初始化器
init(raw
init(rawValue:)
使用指定的原始值創建一個新實例。
聲明
init(rawValue: UInt)
參數
rawValue
用於新實例的原始值。
詳述
如果沒有與指定原始值對應的類型的值,則此初始化程序返回 nil
。例如:
enum PaperSize: String {
case A4, A5, Letter, Legal
}
print(PaperSize(rawValue: "Legal"))
// Prints "Optional("PaperSize.Legal")"
print(PaperSize(rawValue: "Tabloid"))
// Prints "nil"
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 String.Encoding init(rawValue:)。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。