Question

如何将DateComponents转换为Date对象。目前，我有以下代码

Calendar.date(from: DateComponents(year: 2018, month: 1, day: 15))

但是我收到错误说明"No 'date' candidates produce the expected contextual result type 'Date'

对不起基本问题，但我仍然在努力解决如何使用Swift中的日期

Answer 1

您无法在该类型上调用date(from。您必须使用日历的实例，current日历

Calendar.current.date(from: DateComponents(year: 2018, month: 1, day: 15))

或固定的

let calendar = Calendar(identifier: .gregorian)
calendar.date(from: DateComponents(year: 2018, month: 1, day: 15))

Answer 2

//create an instance of DateComponents to keep your code flexible
var dateComponents = DateComponents()

//create the date components
dateComponents.year = 2018
dateComponents.month = 1
dateComponents.day = 15
//dateComponents.timeZone = TimeZone(abbreviation: "EST")
dateComponents.hour = 4
dateComponents.minute = 12

//make something useful out of it
func makeACalendarObject(){

//create an instance of a Calendar for point of reference ex: myCalendar, and use the dateComponents as the parameter
let targetCalendar = Calendar.current
let newCalendarObject = targetCalendar.date(from: dateComponents)


guard let newCalObject = newCalendarObject else {
    return
}
print(newCalObject)
}
//call the object
makeACalendarObject()

Swift - 从月，日，年组件获取日期

2 个答案: