Question

我从API获取一个字符串，其中包含日期和时间为：

 createdAt = "2019-08-12T10:34:05.000Z"

我还需要从该字符串和时间中提取日期。又如何获得两个给定日期字符串之间的时间差？

例如如果我有两个字符串：

StartedOn = "2019-08-12T10:32:18.000Z"
StopedOn = "2019-08-12T10:34:05.000Z".

如何获得从开始到停止的时间。

swift 4，Xcode 10

Answer 1

尝试使用：D

import datetime

StartedOn = "2019-08-12T10:32:18.000Z"
StopedOn = "2019-08-12T10:34:05.000Z"     
StartedOn = datetime.datetime.fromisoformat(StartedOn[:-1]) 
StoppedOn = datetime.datetime.fromisoformat(StopedOn[:-1]) 

print(StoppedOn - StartedOn)

Answer 2

使用 DateFormatter 从Date中获取String实例，即

let str = "2019-08-12T10:34:05.000Z"
let formatter = DateFormatter()
formatter.locale = Locale(identifier: "en_US_POSIX")
formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
let date = formatter.date(from: str)

现在，要获取时差，请将timeIntervalSince(_:)与2个Date对象一起使用，即

let startedOn = "2019-08-12T10:32:18.000Z"
let stoppedOn = "2019-08-12T10:34:05.000Z"
if let startedOnDate = formatter.date(from: startedOn), let stoppedOnDate = formatter.date(from: stoppedOn) {
    let timeInterval = stoppedOnDate.timeIntervalSince(startedOnDate)
    print(timeInterval)
}

如果您需要2个Date对象之间更详细的组件，请像这样使用Calendar对象，

if let startedOnDate = formatter.date(from: startedOn), let stoppedOnDate = formatter.date(from: stoppedOn) {
    let calendar = Calendar(identifier: .gregorian)
    let components = calendar.dateComponents([.hour, .minute, .second], from: startedOnDate, to: stoppedOnDate)
    print(components) //hour: 0 minute: 1 second: 47
}

编辑：

要将date和time与Date对象分开，

let str = "2019-08-12T10:34:05.000Z"
let formatter = DateFormatter()
formatter.locale = Locale(identifier: "en_US_POSIX")
formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
if let date = formatter.date(from: str) {
    formatter.dateFormat = "hh:mm:ss a"
    let timeStr = formatter.string(from: date)
    print(timeStr) //add timeStr to your timeLabel here...

    formatter.dateFormat = "yyyy-MM-dd"
    let dateStr = formatter.string(from: date)
    print(dateStr) //add dateStr to your dateLabel here...
}

Answer 3

有两个专用的日期格式化程序，ISO8601DateFormatter用于将ISO8601字符串转换为Date

let isoFormatter = ISO8601DateFormatter()
isoFormatter.formatOptions = [.withInternetDateTime, .withFractionalSeconds]

let createdAtDate = isoFormatter.date(from: "2019-08-12T10:34:05.000Z")

let startedOn = "2019-08-12T10:32:18.000Z"
let stopedOn = "2019-08-12T10:34:05.000Z"
let startedOnDate = isoFormatter.date(from: startedOn)!
let stopedOnDate = isoFormatter.date(from: stopedOn)!

和DateComponentsFormatter从开始日期和结束日期之间的差值中获取一个m:ss字符串

let componentsFormatter = DateComponentsFormatter()
componentsFormatter.allowedUnits = [.minute, .second]
let duration = componentsFormatter.string(from: startedOnDate, to: stopedOnDate)

如何从标准datetime格式提取日期和时间？

3 个答案: