Skip to main content

Convert a Unix timestamp to a .NET DateTime

The POSIX time, or Unix time, is the number of seconds elapsed from the midnight of January 1st 1970 in UTC coordinates.
This timestamp is used in all *nix languages; probably you will never need to use a Unix timestamp in .NET, but if you have to interact with other application or sites, maybe built in PHP or Java, you will probably have to deal with it.
But .NET doesn't have a method to convert a Unix timestamp to a DateTime and viceversa (or I didn't find it), so I had to implement it.
static DateTime ConvertFromUnixTimestamp(double timestamp)
{
    DateTime origin = new DateTime(1970, 1, 1, 0, 0, 0, 0);
    return origin.AddSeconds(timestamp);
}


static double ConvertToUnixTimestamp(DateTime date)
{
    DateTime origin = new DateTime(1970, 1, 1, 0, 0, 0, 0);
    TimeSpan diff = date - origin;
    return Math.Floor(diff.TotalSeconds);
}
The first method converts a Unix timestamp to its DateTime equivalent, and the second takes a DateTime and convert it to the Unix time.
And in order to get the current timestamp
ConvertToUnixTimestamp(DateTime.UtcNow)
Just a little note on the Unix time: this timestamp is implemented in most systems as a signed 32-bit integer, so can represent only dates in a the range −2,147,483,648 to +2,147,483,647, which means that on January 19th, 2038 the timestamp will overflow, bringing the date back to December 13th, 1901. This is known as Year 2038 problem. Hopefully most of the application we are building now will not last that long.


Ref : http://codeclimber.net.nz/archive/2007/07/10/convert-a-unix-timestamp-to-a-.net-datetime.aspx
http://hassakarn.com/2012/10/10/convert-datetime-to-unix-timestamp-in-c/

Comments

  1. not a developer, I usually convert unix timestamp to human readable date using this free online tool: http://unixresources.net/

    ReplyDelete

Post a Comment

Popular posts from this blog

ASP.NET MVC - Set custom IIdentity or IPrincipal

Here's how I do it. I decided to use IPrincipal instead of IIdentity because it means I don't have to implement both IIdentity and IPrincipal. Create the interface interface ICustomPrincipal : IPrincipal { int UserId { get ; set ; } string FirstName { get ; set ; } string LastName { get ; set ; } } CustomPrincipal public class CustomPrincipal : ICustomPrincipal { public IIdentity Identity { get ; private set ; } public bool IsInRole ( string role ) { return false ; } public CustomPrincipal ( string email ) { this . Identity = new GenericIdentity ( email ); } public int UserId { get ; set ; } public string FirstName { get ; set ; } public string LastName { get ; set ; } } CustomPrincipalSerializeModel - for serializing custom information into userdata field in FormsAuthenticationTicket object. public class CustomPrincipalSerializeMode...

Validate credit card number with Mod 10 algorithm in C#

Introduction All you know what information contains in your NIC number. But do you know what information contains in the Credit Card Number? Following article provides brief details about what information contain in your credit card and demonstrates to how to validate credit card number using mod 10 (Luhn) algorithms with C#. Background  Card Length   Typically, credit card numbers are all numeric and the length of the credit card number is between 12 digits to 19 digits.  14, 15, 16 digits – Diners Club 15 digits – American Express 13, 16 digits – Visa 16 digits - MasterCard   For more information please refer  http://en.wikipedia.org/wiki/Bank_card_number . Hidden information  Major Industry Identifier (MII)   The first digit of the credit card number is the Major Industry Identifier (MII). It designates the category of the entry which issued the card.     1 and 2 – Airlin...

Web Services Description Language Tool (Wsdl.exe)

Ref:  https://msdn.microsoft.com/en-us/library/7h3ystb6(VS.80).aspx The Web Services Description Language tool generates code for XML Web services and XML Web service clients from WSDL contract files, XSD schemas, and .discomap discovery documents. wsdl [options] {URL | path} Argument Description URL The URL to a WSDL contract file (.wsdl), XSD schema file (.xsd), or discovery document (.disco). Note that you cannot specify a URL to a .discomap discovery document. Path The path to a local WSDL contract file (.wsdl), XSD schema file (.xsd), or discovery document (.disco or .discomap). Option Description /appsettingurlkey: key or /urlkey: key Specifies the configuration key to use in order to read the default value for the URL property when generating code. When using the   /parameters   option, this value is the   <appSettingUrlKey>   element and contains a string. /appsettingbaseurl: baseurl or /baseurl:...