如何在swift 3中将日期范围转换为字符串？

Question

如何将日期转换为字符串格式？

我得到两个日期之间的日期（从开始到结束日期）。我正在使用以下方法

class Dates {
static func printDatesBetweenInterval(_ startDate: Date, _ endDate: Date) {
    var startDate = startDate
    let calendar = Calendar.current

    let fmt = DateFormatter()
    fmt.dateFormat = "yyyy-MM-dd"

    while startDate <= endDate {
        print(fmt.string(from: startDate))
        startDate = calendar.date(byAdding: .day, value: 1, to: startDate)!
    }
}

static func dateFromString(_ dateString: String) -> Date {
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = "yyyy-MM-dd"

    return dateFormatter.date(from: dateString)!
}}

在这里打印日期

Dates.printDatesBetweenInterval(Dates.dateFromString("2017-10-02"), Dates.dateFromString("2017-10-9"))

结果：

2017-10-02 2017-10-03 2017-10-04 2017-10-05 2017-10-06 2017-10-07 2017-10-08 2017-10-09

现在，我想将此日期以字符串格式传递给日历（我在应用程序中使用 FSCalendar 库）。我想要这种格式 示例：

["2017-10-02", "2017-10-03", "2017-10-04", "2017-10-05", "2017-10-06", "2017-10-07", "2017-10-08", "2017-10-09"]

谁能指导我。谢谢

Answer 1

从你的函数返回日期字符串数组，像这样：

class Dates {
static func printDatesBetweenInterval(_ startDate: Date, _ endDate: Date) -> [String] {
    var startDate = startDate
    let calendar = Calendar.current

    let fmt = DateFormatter()
    fmt.dateFormat = "yyyy-MM-dd"

    var arrayDateString = [String]()

    while startDate <= endDate {
        let stringDate = fmt.string(from: startDate)
        print("stringDate - \(stringDate)")
        arrayDateString.append(stringDate)
        startDate = calendar.date(byAdding: .day, value: 1, to: startDate)!
    }

   return arrayDateString
}

static func dateFromString(_ dateString: String) -> Date {
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = "yyyy-MM-dd"

    return dateFormatter.date(from: dateString)!
}}

现在，打印字符串数组

let dateStringArray = Dates.printDatesBetweenInterval(Dates.dateFromString("2017-10-02"), Dates.dateFromString("2017-10-9"))

print("dateStringArray - \(dateStringArray)")

编辑：
现在，正如您所说，您拥有以下格式的数据：

let dataArray = [ 
 { "hlddate": "07-Aug", "frmdt": "07-Aug-2017", "todt": "07-Aug-2017" }, 
 { "hlddate": "15-Aug", "frmdt": "15-Aug-2017", "todt": "15-Aug-2017" }, 
 { "hlddate": "10-Oct", "frmdt": "10-Oct-2017","todt": "31-Oct-2017" } 
]

尝试以下解决方案（复制粘贴、dataAray 和类结构并查看结果）：

class Dates {

static func dateFromString(dateString: String, webResponseDateFormat: String = "yyyy-MM-dd") -> Date? {
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = webResponseDateFormat
    return dateFormatter.date(from: dateString)
 }}

 static func printDatesBetweenInterval(startDate: Date, endDate: Date, requiredDateFormat: String = "yyyy-MM-dd") -> [String] {
    var startDate = startDate
    let calendar = Calendar.current

    let fmt = DateFormatter()
    fmt.dateFormat = requiredDateFormat

    var arrayDateString = [String]()

    while startDate <= endDate {
        let stringDate = fmt.string(from: startDate)
        print("stringDate - \(stringDate)")
        arrayDateString.append(stringDate)
        startDate = calendar.date(byAdding: .day, value: 1, to: startDate)!
    }

   return arrayDateString
 }


if let stringDateArray = dataArray as? [[String : String]] {

   for arrayElement in stringDateArray {

       if let startDateString = arrayElement["frmdt"], let startDate = Dates.dateFromString(dateString: startDateString, webResponseDateFormat: "dd-MMM-yyyy"), let endDateString = arrayElement["todt"], let endDate = Dates.dateFromString(dateString: endDateString, webResponseDateFormat: "dd-MMM-yyyy") {

           let dateStringArray = Dates.printDatesBetweenInterval(startDate: startDate, endDate: endDate, )

           print("\n\n**\ndateStringArray - \(dateStringArray)")
       }
   }

}

最终更新

// Actual data structure
let dataArray = ["07-8-2017","08-08-2017","10-09-2017","20-10-2017",21-10-2017","23-10-2017", etc..] 

使用上述方法并在服务器响应部分更改数据并获取结果。

if let Streams = jsonDict["data"] as! [AnyObject]? {

   for arrayElement in Streams {

        if let startDateString = arrayElement["frmdt"] {
             self.somedateFromString = self.convertStringToDate(string: startDateString as! String)

            if  let endDateString = arrayElement["todt"] {
                self.somedateEndString = self.convertStringToDate(string: endDateString as! String)
            }

   self.presentdays = Dates.printDatesBetweenInterval(Dates.dateFromString(self.somedateFromString), Dates.dateFromString(self.somedateEndString))

        self.totalHolidays.append(contentsOf: self.presentdays)

     }
  }
}

Answer 2

static func getDatesStringBetweenInterval(_ startDate: Date, _ endDate: Date)-> String {
        var retval = "["

        var startDate = startDate
        let calendar = Calendar.current

        let fmt = DateFormatter()
        fmt.dateFormat = "yyyy-MM-dd"

        while startDate <= endDate {
            if startDate < endDate {
                retval.append("\"\(fmt.string(from: startDate))\", ")
            } else {
               retval.append("\"\(fmt.string(from: startDate))\"")
            }
            startDate = calendar.date(byAdding: .day, value: 1, to: startDate)!
        }
        retval.append("]")

        return retval
    }

用法：

let aDate = Dates.dateFromString("2017-01-01")
let bDate = Dates.dateFromString("2017-01-05")
let datesString = Dates.getDatesStringBetweenInterval(aDate, bDate)
print(datesString)