如何在 swift 中从两天中获取日期名称

Posted 2023-03-12

【中文标题】如何在 swift 中从两天中获取日期名称

【英文标题】：How get days name from two days in swift

【发布时间】：2019-05-28 12:59:37

【问题描述】：

我有两个日期，date1 和 date2，我想要 date1 和 date 2 之间的天数

例子：

let date1 = 28-May-2019,
let date2 = 31-May-2019

预期输出

[周二、周三、周五]

【问题讨论】：

***.com/questions/32536612/… 然后将这些“Date”的对象转换成你想要的字符串表示形式。

【参考方案1】：

    let date1Str = "28-May-2019"
    let date2Str = "31-May-2019"

    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = "dd-MM-yyyy"
    dateFormatter.locale = Locale(identifier: "en_US")

    var date1 = dateFormatter.date(from:date1Str)!
    var date2 = dateFormatter.date(from:date2Str)!

    let dayFormatter = DateFormatter()
    dayFormatter.dateFormat = "EEE"

    while date1 <= date2 
        let dayInWeek = dayFormatter.string(from: date1)
        print(dayInWeek)
        date1 = Calendar.current.date(byAdding: .day, value: 1, to: date1)!
    

【参考方案2】：

以下代码为您提供两个日期之间的天数，并应说明日历的诡计。

let calendar = Calendar.current
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "dd-MMM-yyyy"
let dayFormatter = DateFormatter()
dayFormatter.dateFormat = "EEE"
let dateFrom = dateFormatter.date(from: "28-May-2019")!
let dateTo = dateFormatter.date(from: "31-May-2019")!


var days: [String] = []
var date = dateFrom
while date <= dateTo 
    let day = dayFormatter.string(from: date)
    days.append(day)
    date = calendar.date(byAdding: .day, value: 1, to: date)!

print(days)

【参考方案3】：

试试这个 -

func getWeekdays(dateOne firstDateStr: String, dateTwo secondDateStr: String) -> [String] 

    let dateformatter = DateFormatter()
    dateformatter.dateFormat = "dd-MMM-yyyy"

    guard let firstDate = dateformatter.date(from: firstDateStr),
        let secondDate = dateformatter.date(from: secondDateStr) else 
            return []
    

    let calendar = Calendar.current
    let numberOfDays: Int

    if firstDate > secondDate 
        numberOfDays = (calendar.dateComponents([.day], from: secondDate, to: firstDate).day ?? 0)
     else 
        numberOfDays = (calendar.dateComponents([.day], from: firstDate, to: secondDate).day ?? 0)
    
    dateformatter.dateFormat = "EEE"

    let days = (0...numberOfDays).compactMap  day -> String? in
        if let date = calendar.date(byAdding: .day, value: day, to: firstDate) 
            return dateformatter.string(from: date)
        
        return nil
    
    print(days)

    return days

【讨论】：

不要硬编码自己的工作日名称。使用DateFormatter 或使用Calendar 中的各种工作日名称属性获取名称。