时间戳与时间互相转换 聊天消息通用

# Swift

func timestampChangeToTimeString(_ timestamp: TimeInterval) -> String {
    let dateFormatter: DateFormatter = DateFormatter()
    let dateBefore = Date(timeIntervalSince1970: timestamp)
    let before = NSCalendar.current.dateComponents([.year, .month, .day, .hour, .minute, .second, .weekOfYear, .weekday, .weekdayOrdinal], from: dateBefore)
    let now = NSCalendar.current.dateComponents([.year, .month, .day, .hour, .minute, .second, .weekOfYear, .weekday, .weekdayOrdinal], from: Date())
    
    if before.year == now.year  {
        if before.month == now.month {
            if before.day == now.day {
                if before.minute! < 5{
                    return "刚刚"
                }else if before.hour! < 1{
                    return "\(String(describing: before.minute))分钟之前"
                }else if before.hour! < 5 && before.hour! >= 1{
                    return "\(String(describing: before.hour))小时之前"
                }else{
                    dateFormatter.dateFormat = "HH:mm"
                }
            } else if before.day! + 1 == now.day {
                dateFormatter.dateFormat = "昨天 HH:mm"
            } else if before.day! + 2 == now.day {
                dateFormatter.dateFormat = "前天 HH:mm"
            } else {
                dateFormatter.dateFormat = "MM-dd HH:mm"
            }
        } else {
            dateFormatter.dateFormat = "MM-dd HH:mm"
        }
    } else {
        dateFormatter.dateFormat = "yyyy-MM-dd HH:mm"
    }
    return dateFormatter.string(from: dateBefore)
}

# 简单使用  

        //时间戳
        let timeStamp = 1515666666
        let timeInterval:TimeInterval = TimeInterval(timeStamp)
        print("时间戳转化为对应的时间=====\(timestampChangeToTimeString(timeInterval))")


 # 当然我们网络数据解析多为String 方法略做更改就可使用
 # 更改后的方法 
   func timestampChangeToTimeStringsss(_ timeStr: String) -> String {
        let dateFormatter: DateFormatter = DateFormatter()
        let timeInterval:TimeInterval = TimeInterval(timeStr)!
        let dateBefore = Date(timeIntervalSince1970:timeInterval)
        ........
     }

# 更改后的使用
        print("时间戳转化为对应的时间========\(timestampChangeToTimeStringsss("1515666666"))")