There is this example code, but then it starts talking about millisecond / nanosecond problems.
The same question is on MSDN, Seconds since the Unix epoch in C#.
This is what I've got so far:
public Double CreatedEpoch
{
get
{
DateTime epoch = new DateTime(1970, 1, 1, 0, 0, 0, 0).ToLocalTime();
TimeSpan span = (this.Created.ToLocalTime() - epoch);
return span.TotalSeconds;
}
set
{
DateTime epoch = new DateTime(1970, 1, 1, 0, 0, 0, 0).ToLocalTime();
this.Created = epoch.AddSeconds(value);
}
}
Here's what you need:
public static DateTime UnixTimeStampToDateTime( double unixTimeStamp )
{
// Unix timestamp is seconds past epoch
System.DateTime dtDateTime = new DateTime(1970,1,1,0,0,0,0,System.DateTimeKind.Utc);
dtDateTime = dtDateTime.AddSeconds( unixTimeStamp ).ToLocalTime();
return dtDateTime;
}
Or, for Java (which is different because the timestamp is in milliseconds, not seconds):
public static DateTime JavaTimeStampToDateTime( double javaTimeStamp )
{
// Java timestamp is milliseconds past epoch
System.DateTime dtDateTime = new DateTime(1970,1,1,0,0,0,0,System.DateTimeKind.Utc);
dtDateTime = dtDateTime.AddMilliseconds( javaTimeStamp ).ToLocalTime();
return dtDateTime;
}
The latest version of .NET (v4.6) has added built-in support for Unix time conversions. That includes both to and from Unix time represented by either seconds or milliseconds.
DateTimeOffset:DateTimeOffset dateTimeOffset = DateTimeOffset.FromUnixTimeSeconds(1000);
DateTimeOffset to Unix time in seconds:long unixTimeStampInSeconds = dateTimeOffset.ToUnixTimeSeconds();
DateTimeOffset:DateTimeOffset dateTimeOffset = DateTimeOffset.FromUnixTimeMilliseconds(1000000);
DateTimeOffset to Unix time in milliseconds:long unixTimeStampInMilliseconds = dateTimeOffset.ToUnixTimeMilliseconds();
Note: These methods convert to and from a UTC DateTimeOffset. To get a DateTime representation simply use the DateTimeOffset.UtcDateTime or DateTimeOffset.LocalDateTime properties:
DateTime dateTime = dateTimeOffset.UtcDateTime;