DateTime,DateTimeOffset,Timestamp備忘

1. 測試一

代碼

static void Main(string[] args)
{
    var now_timestamp = DateTimeOffset.Now.ToUnixTimeSeconds();
    var utc_now_timestamp = DateTimeOffset.UtcNow.ToUnixTimeSeconds();
    if (now_timestamp == utc_now_timestamp) Console.WriteLine("always equals");
    Console.WriteLine($"now timestamp ：{now_timestamp}");
    Console.WriteLine($"now timestamp datetime offset：{DateTimeOffset.FromUnixTimeSeconds(now_timestamp)}");
    Console.WriteLine($"now timestamp datetime offset to datetime：{DateTimeOffset.FromUnixTimeSeconds(now_timestamp).DateTime}");
    Console.WriteLine($"now timestamp datetime offset to local datetime：{DateTimeOffset.FromUnixTimeSeconds(now_timestamp).LocalDateTime}");
    Console.WriteLine($"utc_now timestamp ：{utc_now_timestamp}");
    Console.WriteLine($"utc now timestamp datetime offset：{DateTimeOffset.FromUnixTimeSeconds(utc_now_timestamp)}");
    Console.WriteLine($"utc now timestamp datetime offset to datetime：{DateTimeOffset.FromUnixTimeSeconds(utc_now_timestamp).DateTime}");
    Console.WriteLine($"utc now timestamp datetime offset to local datetime：{DateTimeOffset.FromUnixTimeSeconds(utc_now_timestamp).LocalDateTime}");
}

結果

2. 測試二

代碼

static void Main(string[] args)
{
    Test();
}

public static void Test()
{
    //Thread.CurrentThread.CurrentCulture = new CultureInfo("UTC");
    var utc_now = DateTimeOffset.UtcNow;
    var utc_now_timestamp = utc_now.ToUnixTimeSeconds();
    var now = DateTimeOffset.Now;
    var now_timestamp = now.ToUnixTimeSeconds();
    Console.WriteLine($"utc now：{utc_now}");
    Console.WriteLine($"utc now timestamp：{utc_now_timestamp}");
    Console.WriteLine($"now：{now}");
    Console.WriteLine($"now timestamp：{now_timestamp}");

    Console.WriteLine($"datetime now：{DateTime.Now}");
    Console.WriteLine($"datetime utc now：{DateTime.UtcNow}");

    Console.WriteLine("我是分割線---------------");
    var now_convert = ConvertStampToDateTime(now_timestamp);
    Console.WriteLine($"now convert：{now_convert}");
    Console.WriteLine("我是分割線---------------");

    var now_offset = ConvertStampToDateTimeUpgrade(now_timestamp);
    Console.WriteLine($"now offset：{now_offset}");
    Console.WriteLine($"now offset date：{now_offset.Date}");
    Console.WriteLine($"now offset datetime：{now_offset.DateTime}");
    Console.WriteLine($"now offset local datetime：{now_offset.LocalDateTime}");
    Console.WriteLine($"now offset utc datetime：{now_offset.UtcDateTime}");
}

public static DateTime ConvertStampToDateTime(long timestamp)
{
    //var dtStart = TimeZoneInfo.ConvertTime(new DateTime(1970, 1, 1), TimeZoneInfo.Local);
    var dtStart = TimeZone.CurrentTimeZone.ToLocalTime(new DateTime(1970, 1, 1));
    dtStart = TimeZoneInfo.ConvertTimeFromUtc(new DateTime(1970, 1, 1),TimeZoneInfo.Local);
    return dtStart.Add(TimeSpan.FromTicks(long.Parse(timestamp + "0000000")));
}

public static DateTimeOffset ConvertStampToDateTimeUpgrade(long timestamp)
{
    return DateTimeOffset.FromUnixTimeSeconds(timestamp);
}

結果