添加时间间隔.例如小时，分钟和秒 [英] Adding Time Interval. e.g hours, minutes and seconds

问题描述

我从响应中获取时间，以小时，分钟和秒为单位，就像多个对象的"01:32:34"一样.我已将其保存在自定义日期对象中，其中我保存了日期值和字符串值，有大量记录，因此我将其保存在本地数据库中，并在检索到时以格式 1999-12-31 19:01:04 +0000 ，而我也从响应中得到的字符串值是 19:01:04 .现在我想将所有这些值相加以返回一个字符串，例如 1:15:16 ， 00:15:02 ， 00:45:27 应该返回2小时15分45秒.我已经探索了 Calendar.Components.byAdding ，但是那里的方法只允许我添加一个组件，它不接收数组并返回 Date .是否有任何快速的方法来实现这一目标，我想通过一种优雅而适当的方法来实现这一目标，我可以想到一些修复方法，但它们似乎不合适.

I am getting time from the response in hours, minutes and seconds like "01:32:34" of multiple objects. I have saved it in a custom date object, where i am saving the date value and the string value, there are a large number of records so i am saving it in my local db and upon retrieving i get the date value in the format 1999-12-31 19:01:04 +0000 whereas my string value which i am getting from response as well is 19:01:04. now i would like to add all of these values to return a string e.g 1:15:16, 00:15:02, 00:45:27 should return 2 hours 15 minutes 45 seconds. I have explored Calendar.Components.byAdding but the methods there only let me add one single component, it doesn't receive an array and return Date. Is there any swifty way to achieve this, I want to achieve this via an elegant and proper method, i could think of a few fixes but they don't seem appropriate.

推荐答案

我将假设"01:32:34"表示经过时间为5,554秒，而不是上午1:32.因此，我将其转换为 TimeInterval ，而不是 Date :

I’m going to assume that "01:32:34" represents an elapsed time of 5,554 seconds, not 1:32am. So, I’d convert it to a TimeInterval, not a Date:

func timeInterval(from string: String) -> TimeInterval? {
    let components = string.components(separatedBy: ":").map { Double($0) }
    guard 
        components.count == 3,
        let hours = components[0],
        let minutes = components[1],
        let seconds = components[2]
    else { return nil }

    return ((hours * 60) + minutes) * 60 + seconds
}

您可以选择存储原始的"01:32:34"字符串或此值5,554.0.

You can chose to store either the original "01:32:34" string or this value, 5,554.0.

无论如何，然后将这些数字时间间隔相加是微不足道的.为了显示结果 TimeInterval ，您可以使用 DateComponentsFormatter ，例如

Anyway, then adding these numeric time intervals is trivial addition. And to display a resulting TimeInterval, you’d use a DateComponentsFormatter, e.g.

let timeIntervalFormatter: DateComponentsFormatter = {
    let formatter = DateComponentsFormatter()
    formatter.unitsStyle = .positional
    formatter.allowedUnits = [.hour, .minute, .second]
    return formatter
}()

func totalElapsed(_ strings: [String]) -> String? {
    let total = strings.reduce(TimeInterval.zero) { sum, string in
        sum + (timeInterval(from: string) ?? 0)
    }
    return timeIntervalFormatter.string(from: total)
}

let strings = ["1:15:16", "00:15:02", "00:45:27"]

let result = totalElapsed(strings)

02:15:45

02:15:45

或者如果您想要更多(本地化)自然语言表示形式，请使用 .full 中的 unitsStyle :

Or if you want more of a (localized) natural language representation, use unitsStyle of .full:

2小时15分钟45秒

2 hours, 15 minutes, 45 seconds

此方法(使用 TimeInterval ，而不是 Date )的优点在于，它还可以表示超过24小时的间隔.

This approach (using TimeInterval, not Date) has the virtue that it also can represent intervals that exceed 24 hours.

这篇关于添加时间间隔.例如小时，分钟和秒的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！