如何获取当月的开始日期和结束日期（Swift 3）

我正在尝试获取当月的开始日期和结束日期dd/MM/yyyy格式。我尝试使用此扩展中的答案那么问题 https://stackoverflow.com/questions/33605816/first-and-last-day-of-the-current-month-in-swift.但这似乎不是我想要的（格式不同，而且它给了我上个月的最后一个日期和当月的最后一个日期）。有人能帮我吗。

扩展类：

extension Date {
    func startOfMonth() -> Date? {
        let comp: DateComponents = Calendar.current.dateComponents([.year, .month, .hour], from: Calendar.current.startOfDay(for: self))
        return Calendar.current.date(from: comp)!
    }

    func endOfMonth() -> Date? {
        var comp: DateComponents = Calendar.current.dateComponents([.month, .day, .hour], from: Calendar.current.startOfDay(for: self))
        comp.month = 1
        comp.day = -1
        return Calendar.current.date(byAdding: comp, to: self.startOfMonth()!)
    }
}

我的结构：

struct Constants{

    // keys required for making a Login call (POST Method)
    struct LoginKeys {
       .....
    }

    struct RankingKeys {

        static let DateFrom = String(describing: Date().startOfMonth()) //giving me 2016-11-30 16:00:00 +0000 
        static let DateTo  = String(describing: Date().endOfMonth())
//2016-12-30 16:00:00 +0000
    }
}

预期结果：

DateFrom  = "01/12/2016"
DateTo = "31/12/2016"

您应该编写这个简单的代码：

let dateFormatter = DateFormatter()
let date = Date()
dateFormatter.dateFormat = "dd-MM-yyyy"

对于开始日期：

let comp: DateComponents = Calendar.current.dateComponents([.year, .month], from: date)
let startOfMonth = Calendar.current.date(from: comp)!
print(dateFormatter.string(from: startOfMonth))

对于结束日期：

var comps2 = DateComponents()
comps2.month = 1
comps2.day = -1
let endOfMonth = Calendar.current.date(byAdding: comps2, to: startOfMonth)
print(dateFormatter.string(from: endOfMonth!))