How do I convert a Unix timestamp into a DateTime object in C#.NET?

Unix time, or POSIX time, is the number of seconds elapsed since midnight of January 1, 1970 (UTC).

Here is a utility class that can be used to convert a Unix timestamp into a DateTime object and vice versa:

using System;
 
public static class DateTimeUtility
{
    public static DateTime UnixOrigin
    {
        get { return new DateTime( 1970, 1, 1, 0, 0, 0, 0 ); }
    }
 
    public static DateTime ConvertFromUnixTimestamp( long timestamp )
    {
        return UnixOrigin.AddSeconds( (long)timestamp );
    }
 
    public static long ConvertToUnixTimestamp( DateTime dateTime )
    {
        TimeSpan differnce = dateTime - UnixOrigin;
 
        return (long)differnce.TotalSeconds;
    }
}