swift5 日期所在周开始日期 等

//日期所在周开始日期(星期天)

funcstartOfWeek(ofdate:Date) ->Date? {

    letcalendar =NSCalendar.current

    letcomponents = calendar.dateComponents([.yearForWeekOfYear, .weekOfYear],from: date)

    letstartOfWeek = calendar.date(from: components)

    returnstartOfWeek

}

//日期所在周结束日期(星期六)

funcendOfWeek(ofdate:Date) ->Date? {

    guardletstartOfWeek = startOfWeek(of: date)else{returnnil}

    letcalendar =NSCalendar.current

    varcomponents =DateComponents()

    components.day=7

    components.second= -1

    letendOfWeek = calendar.date(byAdding: components,to: startOfWeek)

    returnendOfWeek

}

//日期所在月开始日期

funcstartOfMonth(ofdate:Date) ->Date? {

    letcalendar =NSCalendar.current

    letcomponents = calendar.dateComponents([.year, .month],from: date)

    letstartOfMonth = calendar.date(from: components)

    returnstartOfMonth

}

//日期所在月结束日期

funcendOfMonth(ofdate:Date) ->Date? {

    guardletstartOfMonth = startOfMonth(of: date)else{returnnil}

    letcalendar =NSCalendar.current

    varcomponents =DateComponents()

    components.month=1

    components.second= -1

    letendOfMonth = calendar.date(byAdding: components,to: startOfMonth)

    returnendOfMonth

}

//日期所在年开始日期

funcstartOfYear(ofdate:Date) ->Date? {

    letcalendar =NSCalendar.current

    letcomponents = calendar.dateComponents([.year],from: date)

    letstartOfYear = calendar.date(from: components)!

    returnstartOfYear

}

//日期所在年结束日期

funcendOfYear(ofdate:Date) ->Date? {

    guardletstartOfYear = startOfYear(of: date)else{returnnil}

    letcalendar =NSCalendar.current

    varcomponents =DateComponents()

    components.year=1

    components.second= -1

    letendOfYear = calendar.date(byAdding: components,to: startOfYear)

    returnendOfYear

}

functest() {

    guardletstart = startOfWeek(of:Date())?.timeIntervalSince1970else{return}

    print("start:\(start)")

    guardletend = endOfWeek(of:Date())?.timeIntervalSince1970else{return}

    print("end:\(end)")

    guardletstartOfMonth = startOfMonth(of:Date())?.timeIntervalSince1970else{return}

    print("startOfMonth:\(startOfMonth)")

    guardletendOfMonth = endOfMonth(of:Date())?.timeIntervalSince1970else{return}

    print("endOfMonth:\(endOfMonth)")

    guardletstartOfYear = startOfYear(of:Date())?.timeIntervalSince1970else{return}

    print("startOfYear:\(startOfYear)")

    guardletendOfYear = endOfYear(of:Date())?.timeIntervalSince1970else{return}

    print("endOfYear:\(endOfYear)")

}