swift日期操作

简介：本文将介绍一些关于swift中对于日期的格式化与获取，支持swift4.0

extension Date {
    
    //格式化日期
    func getDateString() -> String{
        let  dateFormater = DateFormatter.init()
        //EEEE:星期几
        //YYYY:年份
        //MM:月份
        //dd:几号
        //HH:小时
        //mm:分钟
        //ss:秒
        //zzz:时区号
        
        dateFormater.dateFormat = "EEEE-YYYY-MM-dd HH:mm:ss:zzz"
        let dateStr = dateFormater.string(from: self)
        
        return dateStr
    }
    
    //获取某个日期为星期几
    func getDateWeekday() ->String{
        let weekdaysTitleArr = ["周日","周一","周二","周三","周四","周五","周六"]
        let timeInterval:TimeInterval = self.timeIntervalSince1970
        let days = Int(timeInterval/86400)
        let weekday = ((days + 4)%7+7)%7
        return weekdaysTitleArr[weekday]
    }
    
    //将日期转换为时间戳(10位)
    func getTimeStamp() -> Int{
        let timeInterval:TimeInterval = self.timeIntervalSince1970
        let timeStamp = Int(timeInterval)
        return timeStamp
    }
}

class Utility: NSObject {

    //根据时间戳获取时间字符串
    class func getDateStringFromTimestamp(_ timestamp:Int64) ->String{
        let timeInterval:TimeInterval = TimeInterval(timestamp)
        let date = Date(timeIntervalSince1970: timeInterval)
        return date.getDateString()
    }
    
    //根据时间戳获取日期对象
    class func getDateFromTimestamp(_ timestamp:Int64) ->Date{
        let timeInterval:TimeInterval = TimeInterval(timestamp)
        let date = Date(timeIntervalSince1970: timeInterval)
        return date
    }
    
    //获取两个日期的间隔天数
    class func getDateInterval(dateA:Date,dateB:Date) ->Int{
        let interval = dateA.timeIntervalSince(dateB)
        let days = Int(interval/(24*60*60))
//        let hours = Int(interval/(60*60))
//        let mins = Int(interval/60)
        return days
    }
}

最后就是方法的调用与后台的输出

        let date = Date()
        print(date.getDateString())
        print(date.getDateWeekday())
        print(date.getTimeStamp())
        
        let dateA = Utility.getDateFromTimestamp(1507605071)
        let dateB = Utility.getDateFromTimestamp(1507877163)
        let days = Utility.getDateInterval(dateA: dateA, dateB: dateB)
        print(days)    

PS:   http://tool.chinaz.com/Tools/unixtime.aspx   这个网址可以在线转换时间戳