I Want Convert My Datetime to TimeStamp C#?

Question

I want to convert my datetime in C# (eg 2009-06-22 16:35:16.000 ) to something like this 1196550000000 . I tried the following method but it fails.

public static double GetTimestamp(DateTime value)
{
    long ticks = DateTime.UtcNow.Ticks - DateTime.Parse(value.ToString()).Ticks;
    ticks /= 10000000; //Convert windows ticks to seconds
    Int64 timestamp = ticks;
    return timestamp;
}

Answer 1

First of all, you don't need to ToString() and Reparse the DateTime . If you want just the Date you can use the DateTime.Date property.

Then, this should be simple enough (using DateTime.Now as a reference point):

public static double GetTimestamp(DateTime value)
{
    return new TimeSpan(DateTime.UtcNow.Ticks - value.Ticks).TotalSeconds;
}

In case the parsing you did in your question did refer to extracting the date from the DateTime , you can use the following:

public static double GetTimestamp(DateTime value)
{
     return new TimeSpan(DateTime.UtcNow.Ticks - value.Date.Ticks).TotalSeconds;
}

EDIT : You appear to want some kind of posix time conversion which can be achieved like this :

private static readonly DateTime POSIXRoot = new DateTime(1970, 1, 1, 0, 0, 0, 0);
public static double GetPosixSeconds(DateTime value)
{
    return (value - POSIXRoot).TotalSeconds;
}

public static DateTime GetDateTime(double posixSeconds) {
    return POSIXRoot.AddSeconds(posixSeconds);
}