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struct RelativeFormatStyleUse the strings that the format style produces, such as “1 hour ago”, “in 2 weeks”, “yesterday”, and “tomorrow” as standalone strings. Embedding them in other strings may not be grammatically correct. それらを他の文字列の中に埋め込むことは、文法的に正しくないかもしれません。
Express relative date formats in either numeric or named styles. For example:
例えば：
if let past = Calendar.current.date(byAdding: .day, value: -7, to: Date()) {
var formatStyle = Date.RelativeFormatStyle()
formatStyle.presentation = .numeric
past.formatted(formatStyle) // "1 week ago"
formatStyle.presentation = .named
past.formatted(formatStyle) // "last week"
}Use the convenient static factory method relative(presentation: to shorten the syntax when applying presentation and units style modifiers to customize the format. For example:
例えば：
if let past = Calendar.current.date(byAdding: .day, value: 7, to: Date()) {
past.formatted(.relative(presentation: .numeric)) // "in 1 week"
past.formatted(.relative(presentation: .named)) // "next week"
past.formatted(.relative(presentation: .named, unitsStyle: .wide)) // "next week"
past.formatted(.relative(presentation: .named, unitsStyle: .narrow)) // "next wk."
past.formatted(.relative(presentation: .named, unitsStyle: .abbreviated)) // "next wk."
past.formatted(.relative(presentation: .named, unitsStyle: .spellOut)) // "next week"
past.formatted(.relative(presentation: .numeric, unitsStyle: .wide)) // "in 1 week"
past.formatted(.relative(presentation: .numeric, unitsStyle: .narrow)) // "in 1 wk."
past.formatted(.relative(presentation: .numeric, unitsStyle: .abbreviated)) // "in 1 wk."
past.formatted(.relative(presentation: .numeric, unitsStyle: .spellOut)) // "in one week"
}The format(_:) instance method generates a string from the provided relative date.
format(_:)インスタンスメソッドは、ある文字列をこの提供された相対日付から生成します。
Once you create a style, you can use it to format relative dates multiple times.
The following example applies a format style repeatedly to produce string representations of relative dates:
if let pastWeek = Calendar.current.date(byAdding: .day, value: -7, to: Date()),
let pastDay = Calendar.current.date(byAdding: .day, value: -1, to: Date()) {
let formatStyle = Date.RelativeFormatStyle(
presentation: .named,
unitsStyle: .spellOut,
locale: Locale(identifier: "en_GB"),
calendar: Calendar.current,
capitalizationContext: .beginningOfSentence)
formatStyle.format(pastDay) // "Yesterday"
formatStyle.format(pastWeek) // "Last week"
}init(presentation: Date.RelativeFormatStyle.Presentation, unitsStyle : Date.RelativeFormatStyle.UnitsStyle, locale: Locale, calendar: Calendar, capitalizationContext : FormatStyleCapitalizationContext) static func relative(presentation: Presentation, unitsStyle : UnitsStyle) -> Date.RelativeFormatStyle var presentation: Date.RelativeFormatStyle.Presentation var unitsStyle : Date.RelativeFormatStyle.UnitsStyle var calendar: Calendarvar capitalizationContext : FormatStyleCapitalizationContext var locale: Localefunc locale(Locale) -> Date.RelativeFormatStyle func format(Date) -> Stringinit(from: Decoder)func encode(to: Encoder)var hashValue : Intfunc hash(into: inout Hasher)static func != (Date.RelativeFormatStyle, Date.RelativeFormatStyle) -> Bool static func == (Date.RelativeFormatStyle, Date.RelativeFormatStyle) -> Bool struct Date.RelativeFormatStyle.Presentation struct Date.RelativeFormatStyle.UnitsStyle