C#使用各種時間戳及轉換

/// <summary>
/// DateTime時間格式轉換為13位帶毫秒的Unix時間戳
/// </summary>
/// <param name="time">DateTime時間格式</param>
/// <returns>Unix時間戳格式</returns>
public static long ConvertDateTimeLong(DateTime time)
{
    DateTime startTime = TimeZone.CurrentTimeZone.ToLocalTime(new DateTime(1970, 1, 1));
    return (long)(time - startTime).TotalMilliseconds;
}

/// <summary>
/// DateTime時間格式轉換為10位不帶毫秒的Unix時間戳
/// </summary>
/// <param name="time">DateTime時間格式</param>
/// <returns>Unix時間戳格式</returns>
public static long ConvertDateTimeInt(DateTime time)
{
    DateTime startTime = TimeZone.CurrentTimeZone.ToLocalTime(new DateTime(1970, 1, 1));
    return (long)(time - startTime).TotalSeconds;
}

/// <summary>
/// 時間戳轉為C#格式時間
/// </summary>
/// <param name="timeStamp">Unix時間戳格式</param>
/// <returns>C#格式時間</returns>
public static DateTime GetTime(string timeStamp)
{
    DateTime dtStart = TimeZone.CurrentTimeZone.ToLocalTime(new DateTime(1970, 1, 1));
    long lTime = long.Parse(timeStamp + "0000000");
    TimeSpan toNow = new TimeSpan(lTime);
    return dtStart.Add(toNow);
}